Help... Logfile is being filled up rapidly with a (to me) unclear message, and it does it multiple times per second

In Nextcloud, in the Log Reader app I see this:

[no app in context] Warning: Temporary directory /tmp/nextcloudtemp is not present or writable GET /apps/logreader/poll?lastReqId=[string] from [IP address] by [user name] at 2020-03-09T16:46:07+00:00

The log file is being filled up rapidly with these messages, multiple times per second.
The folder exists, Apache is the owner of the folder, and I have even set 777 chmod-rights, and I have rebooted the server…

Still, the message persists. Multiple times per second.

After this I checked my /var/www/data/nextcloud.log, and it is currently at 68MB and rising.

This is stated in my config.php:
'tempdirectory' => '/tmp/nextcloudtemp',

Anyone any tips?

Nextcloud version: 18.0.1
Operating system and version: CentOS 7.7.1908
Apache or nginx version: Apache 2.4.6
PHP version: 7.3.15
Database: 5.5.64-MariaDB MariaDB Server

You can make a other tmp directory.
‘tempdirectory’ => ‘/tmp’,

I could. And I did.
Didn’t work.

Thanks anyway.

I seem to have solved it. Kind of. I don’t think this is what one would call ‘best practice’ though…

Nothing what I did to or in the directory /tmp worked. Nothing. Don’t understand why. Changed ownership and read/write/execute rights… Nothing.
(While each time specifying the temp directory in the config.php…)

Just for the test I made the temp folder location /var/www/nextcloudtemp, next to the Nextcloud data folder… Lo and behold… No new error messages are appearing.
The now 74MB logfile has stopped growing.

If anyone has any idea on how/why/what, I’m open to suggestions…

selinux denied access to web server into /tmp?

No. Even with SELinux on ‘disabled’ it doesn’t work.

What permissions are set for the parent folder /tmp? Are they set to xx5 or xx7?

Parent folder /tmp is xx7.

Just now noticed it has a ‘sticky bit’. It’s not rwx rwx rwx, but rwx rwx rwt. But it’s 7 anyway.

Sticky bit on /tmp is expected. It shouldn’t interfere as it keeps users from deleting other user’s files. The webserver should only delete files it has created itself.

But could this answer be related?