No apps in app store

Nextcloud version: 17.0.1
Operating system and version: Ubuntu 18.04
Nginx version: 1.17.6
PHP version: 7.3.12-1

The issue you are facing:
Hi all!
This is a fresh install of NC. My apps store page lists all installed apps, I can enable and disable them, but when I click on a category to install a new one all the list’s are empty. I get no browser error or error notice at all, and this happens across browsers (even incognito), computers, and networks. Also, the error log is not showing anything that seems relevant to this issue.

Is this the first time you’ve seen this error? : No.
This has happened on all my attempts to install NC, with Apache2 and Nginx.

Steps to replicate it:

  1. Fresh install of NC
  2. Go to apps store categories
  3. Ponder on the emptiness.

The output of your Nextcloud log in Admin > Logging:

{"reqId":"5OjX94pCYf0HBRFwaaOZ","level":3,"time":"2019-12-11T20:01:19+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_XlUkPw): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"gUnYu781tuFnyklKusvf","level":3,"time":"2019-12-11T20:01:19+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_Dvlan5): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"yLs7xK27nN2XyMZhA1cS","level":3,"time":"2019-12-11T20:18:36+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_HqkRqd): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"61vDL35mslSH1DojtJ6Z","level":3,"time":"2019-12-11T20:18:36+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_SoWYfd): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"TtFibUUs0qSnsXTHptyC","level":3,"time":"2019-12-11T20:33:55+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_LD9DL8): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"Nx5HPikAzGkPXZiHizbJ","level":3,"time":"2019-12-11T20:33:55+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_JDd0N8): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"e6YsjvazB4oRmVS55uNN","level":3,"time":"2019-12-11T20:34:05+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_cqv0fw): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"OajKclu0CwQc5FH8efRt","level":3,"time":"2019-12-11T20:34:06+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_f1uwVy): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"sKD2NaT02JH6UFkXypv5","level":3,"time":"2019-12-11T20:34:21+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_uzciy6): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"j2ZfiE43AOZZxVL9UdjL","level":3,"time":"2019-12-11T20:40:57+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_RS1q4P): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"S9mljYlFXsITlFgLasuk","level":3,"time":"2019-12-11T20:40:57+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_hQvVJp): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"laCwRF5v2av3RPEacXOX","level":3,"time":"2019-12-11T20:42:40+01:00","remoteAddr":"186.143.201.142","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=500&y=500&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_z6MELN): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (Linux; Android 9; moto g(7) power) AppleWebKit\/537.36 (KHTML, like Gecko) Chrome\/78.0.3904.108 Mobile Safari\/537.36","version":"17.0.1.1"}
{"reqId":"2JLsIaHiwQpCy35UqH7w","level":3,"time":"2019-12-11T20:42:41+01:00","remoteAddr":"186.143.201.142","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_50vocF): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (Linux; Android 9; moto g(7) power) AppleWebKit\/537.36 (KHTML, like Gecko) Chrome\/78.0.3904.108 Mobile Safari\/537.36","version":"17.0.1.1"}
{"reqId":"nwirCmY27V5EYVuVg45e","level":3,"time":"2019-12-11T20:44:59+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_Cw0ijL): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"2nxarCkyumyXmKOgAS2Y","level":3,"time":"2019-12-11T20:44:59+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_lK92wi): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"xtPo8E9IUQOBDnRNYfBc","level":3,"time":"2019-12-11T20:45:10+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview.png?file=\/Nextcloud%20intro.mp4&x=150&y=150&c=543ab2f5b7c7a65a40376201dbea2d01","message":"unlink(\/tmp\/oc_tmp_lp1LPk): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"cuLJQqKfOUXZ19kPttGy","level":3,"time":"2019-12-11T20:45:21+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview.png?file=\/Nextcloud%20intro.mp4&x=150&y=150&c=543ab2f5b7c7a65a40376201dbea2d01","message":"unlink(\/tmp\/oc_tmp_hxKilZ): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"ulVomqVt9ddIepDeX1E2","level":3,"time":"2019-12-11T20:45:49+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_pJfYNE): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"w0ApQrad4jMN333t7SDu","level":3,"time":"2019-12-11T20:45:49+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_7IacTj): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"lTG0AJdYNu2FeoaOObdG","level":3,"time":"2019-12-11T20:47:06+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_BzJ8qr): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"umO6yq4OsWcV3jT1NI69","level":3,"time":"2019-12-11T20:47:06+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_FnMpv3): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"BvqjkrPscXFFXiCK51ce","level":3,"time":"2019-12-11T20:59:38+01:00","remoteAddr":"191.85.164.222","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_HstjKm): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (Windows NT 10.0; Win64; x64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"DxyjG8239tMCjduuaUU2","level":3,"time":"2019-12-11T20:59:38+01:00","remoteAddr":"191.85.164.222","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_F5udBf): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (Windows NT 10.0; Win64; x64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"PtzzubbLXSAHOE6uGWdl","level":3,"time":"2019-12-11T21:03:35+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_Rp1UB1): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"lmp2G5qLWpH6lL6aDbp9","level":3,"time":"2019-12-11T21:03:35+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_K3syvI): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"nSZ0EubJsyYiVa20UD05","level":3,"time":"2019-12-11T21:04:38+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&c=42f965e408887de37c71b8dc5a01944a&x=250&y=250&forceIcon=0","message":"unlink(\/tmp\/oc_tmp_7Io3oe): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"D2Nj95FX32kO14z5J9ek","level":3,"time":"2019-12-11T21:04:38+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"PHP","method":"GET","url":"\/core\/preview?fileId=7&x=32&y=32","message":"unlink(\/tmp\/oc_tmp_fPhKwH): No such file or directory at \/var\/www\/nextcloud\/lib\/private\/Preview\/Movie.php#98","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"454xqAiRiGfXD4zhGizn","level":2,"time":"2019-12-11T21:44:46+01:00","remoteAddr":"192.168.1.69","user":"--","app":"no app in context","method":"POST","url":"\/login","message":"Login failed: admin (Remote IP: 192.168.1.69)","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"vI8RUcDBOUqeGLhs5WrA","level":3,"time":"2019-12-11T21:45:34+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"internet_connection_check","method":"GET","url":"\/settings\/ajax\/checksetup","message":{"Exception":"GuzzleHttp\\Exception\\ConnectException","Message":"cURL error 28: Connection timed out after 30000 milliseconds (see 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***"]},{"file":"\/var\/www\/nextcloud\/3rdparty\/guzzlehttp\/guzzle\/src\/RedirectMiddleware.php","line":70,"function":"GuzzleHttp\\{closure}","class":"GuzzleHttp\\Middleware","type":"::","args":["*** sensitive parameters replaced ***"]},{"file":"\/var\/www\/nextcloud\/3rdparty\/guzzlehttp\/guzzle\/src\/RedirectMiddleware.php","line":107,"function":"__invoke","class":"GuzzleHttp\\RedirectMiddleware","type":"->","args":["*** sensitive parameter replaced ***","*** sensitive parameter replaced ***"]},{"file":"\/var\/www\/nextcloud\/3rdparty\/guzzlehttp\/guzzle\/src\/RedirectMiddleware.php","line":72,"function":"checkRedirect","class":"GuzzleHttp\\RedirectMiddleware","type":"->","args":[{"__class__":"GuzzleHttp\\Psr7\\Request"},"*** sensitive parameter replaced ***","*** sensitive parameter replaced 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***"]},{"file":"\/var\/www\/nextcloud\/3rdparty\/guzzlehttp\/promises\/src\/Promise.php","line":246,"function":"run","class":"GuzzleHttp\\Promise\\TaskQueue","type":"->","args":[true]},{"file":"\/var\/www\/nextcloud\/3rdparty\/guzzlehttp\/promises\/src\/Promise.php","line":223,"function":"invokeWaitFn","class":"GuzzleHttp\\Promise\\Promise","type":"->","args":[]},{"file":"\/var\/www\/nextcloud\/3rdparty\/guzzlehttp\/promises\/src\/Promise.php","line":267,"function":"waitIfPending","class":"GuzzleHttp\\Promise\\Promise","type":"->","args":[]},{"file":"\/var\/www\/nextcloud\/3rdparty\/guzzlehttp\/promises\/src\/Promise.php","line":225,"function":"invokeWaitList","class":"GuzzleHttp\\Promise\\Promise","type":"->","args":[]},{"file":"\/var\/www\/nextcloud\/3rdparty\/guzzlehttp\/promises\/src\/Promise.php","line":62,"function":"waitIfPending","class":"GuzzleHttp\\Promise\\Promise","type":"->","args":[]},{"file":"\/var\/www\/nextcloud\/3rdparty\/guzzlehttp\/guzzle\/src\/Client.php","line":131,"function":"wait","class":"GuzzleHttp\\Promise\\Promise","type":"->","args":[]},{"file":"\/var\/www\/nextcloud\/lib\/private\/Http\/Client\/Client.php","line":144,"function":"request","class":"GuzzleHttp\\Client","type":"->","args":["get","http:\/\/www.nextcloud.com\/",{"proxy":null,"verify":"\/media\/Datos-2\/ncdata\/files_external\/rootcerts.crt","timeout":30,"headers":{"User-Agent":"Nextcloud Server Crawler"},"synchronous":true}]},{"file":"\/var\/www\/nextcloud\/settings\/Controller\/CheckSetupController.php","line":153,"function":"get","class":"OC\\Http\\Client\\Client","type":"->","args":["http:\/\/www.nextcloud.com\/"]},{"file":"\/var\/www\/nextcloud\/settings\/Controller\/CheckSetupController.php","line":136,"function":"isSiteReachable","class":"OC\\Settings\\Controller\\CheckSetupController","type":"->","args":["www.nextcloud.com"]},{"file":"\/var\/www\/nextcloud\/settings\/Controller\/CheckSetupController.php","line":673,"function":"hasInternetConnectivityProblems","class":"OC\\Settings\\Controller\\CheckSetupController","type":"->","args":[]},{"file":"\/var\/www\/nextcloud\/lib\/private\/AppFramework\/Http\/Dispatcher.php","line":170,"function":"check","class":"OC\\Settings\\Controller\\CheckSetupController","type":"->","args":[]},{"file":"\/var\/www\/nextcloud\/lib\/private\/AppFramework\/Http\/Dispatcher.php","line":99,"function":"executeController","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->","args":[{"__class__":"OC\\Settings\\Controller\\CheckSetupController"},"check"]},{"file":"\/var\/www\/nextcloud\/lib\/private\/AppFramework\/App.php","line":126,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->","args":[{"__class__":"OC\\Settings\\Controller\\CheckSetupController"},"check"]},{"file":"\/var\/www\/nextcloud\/lib\/private\/AppFramework\/Routing\/RouteActionHandler.php","line":47,"function":"main","class":"OC\\AppFramework\\App","type":"::","args":["OC\\Settings\\Controller\\CheckSetupController","check",{"__class__":"OC\\AppFramework\\DependencyInjection\\DIContainer"},{"_route":"settings.CheckSetup.check"}]},{"function":"__invoke","class":"OC\\AppFramework\\Routing\\RouteActionHandler","type":"->","args":[{"_route":"settings.CheckSetup.check"}]},{"file":"\/var\/www\/nextcloud\/lib\/private\/Route\/Router.php","line":297,"function":"call_user_func","args":[{"__class__":"OC\\AppFramework\\Routing\\RouteActionHandler"},{"_route":"settings.CheckSetup.check"}]},{"file":"\/var\/www\/nextcloud\/lib\/base.php","line":1000,"function":"match","class":"OC\\Route\\Router","type":"->","args":["\/settings\/ajax\/checksetup"]},{"file":"\/var\/www\/nextcloud\/index.php","line":42,"function":"handleRequest","class":"OC","type":"::","args":[]}],"File":"\/var\/www\/nextcloud\/3rdparty\/guzzlehttp\/guzzle\/src\/Handler\/CurlFactory.php","Line":185,"CustomMessage":"--"},"userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"gSoq95KhxSSzg3XpgyCy","level":2,"time":"2019-12-13T15:31:21+01:00","remoteAddr":"192.168.1.69","user":"--","app":"no app in context","method":"POST","url":"\/login","message":"Login failed: admin (Remote IP: 192.168.1.69)","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"2lCIgop49vMr6D8acFEY","level":2,"time":"2019-12-16T15:42:33+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"core","method":"POST","url":"\/login\/confirm","message":"Login failed: 'admin' (Remote IP: '192.168.1.69')","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"6u9kMJrKOJbLElqipjT7","level":2,"time":"2019-12-16T15:42:45+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"user_ldap","method":"POST","url":"\/apps\/user_ldap\/ajax\/getConfiguration.php","message":"Configuration Error (prefix s01): No LDAP Host given!","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"6u9kMJrKOJbLElqipjT7","level":2,"time":"2019-12-16T15:42:45+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"user_ldap","method":"POST","url":"\/apps\/user_ldap\/ajax\/getConfiguration.php","message":"Configuration Error (prefix s01): No LDAP Port given!","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"6u9kMJrKOJbLElqipjT7","level":2,"time":"2019-12-16T15:42:45+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"user_ldap","method":"POST","url":"\/apps\/user_ldap\/ajax\/getConfiguration.php","message":"Configuration Error (prefix s01): No LDAP Login Filter given!","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"6u9kMJrKOJbLElqipjT7","level":2,"time":"2019-12-16T15:42:45+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"user_ldap","method":"POST","url":"\/apps\/user_ldap\/ajax\/getConfiguration.php","message":"Configuration Error (prefix s01): Not a single Base DN given.","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}
{"reqId":"6u9kMJrKOJbLElqipjT7","level":2,"time":"2019-12-16T15:42:45+01:00","remoteAddr":"192.168.1.69","user":"admin","app":"user_ldap","method":"POST","url":"\/apps\/user_ldap\/ajax\/getConfiguration.php","message":"Configuration Error (prefix s01): login filter does not contain %uid place holder.","userAgent":"Mozilla\/5.0 (X11; Ubuntu; Linux x86_64; rv:71.0) Gecko\/20100101 Firefox\/71.0","version":"17.0.1.1"}

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

{
    "system": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "***REMOVED SENSITIVE VALUE***",
            "***REMOVED SENSITIVE VALUE***"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "17.0.1.1",
        "overwrite.cli.url": "***REMOVED SENSITIVE VALUE***",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "activity_expire_days": 14,
        "auth.bruteforce.protection.enabled": true,
        "blacklisted_files": [
            ".htaccess",
            "Thumbs.db",
            "thumbs.db"
        ],
        "cron_log": true,
        "enable_previews": true,
        "enabledPreviewProviders": [
            "OC\\Preview\\PNG",
            "OC\\Preview\\JPEG",
            "OC\\Preview\\GIF",
            "OC\\Preview\\BMP",
            "OC\\Preview\\XBitmap",
            "OC\\Preview\\Movie",
            "OC\\Preview\\PDF",
            "OC\\Preview\\MP3",
            "OC\\Preview\\TXT",
            "OC\\Preview\\MarkDown"
        ],
        "filesystem_check_changes": 0,
        "filelocking.enabled": "true",
        "htaccess.RewriteBase": "\/",
        "integrity.check.disabled": false,
        "knowledgebaseenabled": false,
        "logfile": "***REMOVED SENSITIVE VALUE***",
        "loglevel": 2,
        "logtimezone": "Europe\/Berlin",
        "log_rotate_size": 104857600,
        "maintenance": false,
        "memcache.local": "\\OC\\Memcache\\APCu",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "overwriteprotocol": "https",
        "preview_max_x": 1024,
        "preview_max_y": 768,
        "preview_max_scale_factor": 1,
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 0,
            "timeout": 0
        },
        "quota_include_external_storage": false,
        "share_folder": "\/Shares",
        "skeletondirectory": "",
        "theme": "",
        "trashbin_retention_obligation": "auto, 7",
        "updater.release.channel": "stable",
        "mail_smtpmode": "smtp",
        "mail_smtpsecure": "tls",
        "mail_sendmailmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauthtype": "LOGIN",
        "mail_smtpauth": 1,
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "apps_paths": [
            {
                "path": "\/var\/www\/nextcloud\/apps",
                "url": "\/apps",
                "writable": false
            },
            {
                "path": "\/var\/www\/nextcloud\/apps2",
                "url": "\/apps2",
                "writable": true
            }
        ],
        "ldapIgnoreNamingRules": false,
        "ldapProviderFactory": "OCA\\User_LDAP\\LDAPProviderFactory"
    },
    

The output of your nginx/system log in /var/log/____:

  GNU nano 2.9.3                                                                             /var/log/nginx/error.log                                                                                       

2019/12/16 10:48:04 [error] 1095#1095: ocsp.int-x3.letsencrypt.org could not be resolved (110: Operation timed out) while requesting certificate status, responder: ocsp.int-x3.letsencrypt.org, certificat$

SOLVED:

The issue was in /lib/private/App/AppStore/Fetcher/Fetcher.php.
Changed the line with " ‘timeout’ => 10 " to " ‘timeout’ => 40 "