My Linux Mint 22.3 system updated from 34.0.0 to 34.0.1 this morning.
The result has not been good so far. The sync client goes into a restart cycle that is not obvious how to stop. Several attempts to kill the process have left the desktop hung and needing a restart.
Logs for the original config:
2026-08-05 11:16:42:332 [ warning default unknown:0 ]: Qt Concurrent has caught an exception thrown from a worker thread.
This is not supported, exceptions thrown in worker threads must be
caught before control returns to Qt Concurrent.
Clearing the config dir and starting from scratch:
2026-08-05 11:17:52:659 [ info nextcloud.gui.application ./src/gui/application.cpp:966 ]: ################## "Nextcloud" locale: "en_GB" ui_lang: QVariant(Invalid) version: "34.0.1-20260805.074743.364596d2ca-1.0\~noble1" os: "Linux Mint 22.3" platform: "xcb"
2026-08-05 11:17:52:659 [ info nextcloud.gui.application ./src/gui/application.cpp:972 ]: Arguments: QList("/usr/bin/nextcloud", "--background")
2026-08-05 11:17:52:659 [ info nextcloud.gui.application ./src/gui/application.cpp:1272 ]: System UI languages are: QList("en-GB", "en-Latn-GB", "en", "en-Latn-US", "en-US")
2026-08-05 11:17:52:659 [ info nextcloud.gui.application ./src/gui/application.cpp:1289 ]: selected application language: "en_GB"
2026-08-05 11:17:52:659 [ info nextcloud.gui.application ./src/gui/application.cpp:1296 ]: Using "en_GB" translation
2026-08-05 11:17:52:659 [ info nextcloud.gui.application ./src/gui/application.cpp:149 ]: This is not an upgrade/downgrade/migration. Proceed to read current application config file.
2026-08-05 11:17:52:659 [ warning nextcloud.gui.application ./src/gui/application.cpp:369 ]: Config version migration was not possible.
2026-08-05 11:17:52:675 [ info nextcloud.gui.application ./src/gui/application.cpp:417 ]: VFS suffix plugin is available
2026-08-05 11:17:52:675 [ info nextcloud.gui.socketapi ./src/gui/socketapi/socketapi.cpp:303 ]: Listen started.
2026-08-05 11:17:52:675 [ info nextcloud.gui.folder.manager ./src/gui/folderman.cpp:74 ]: setting remote poll timer interval to 30000 msec
2026-08-05 11:17:52:676 [ info nextcloud.gui.account.manager ./src/gui/accountmanager.cpp:174 ]: Checking for accounts versions.
2026-08-05 11:17:52:676 [ info nextcloud.gui.account.manager ./src/gui/accountmanager.cpp:175 ]: Config accounts version: 0
2026-08-05 11:17:52:676 [ info nextcloud.gui.account.manager ./src/gui/accountmanager.cpp:176 ]: Max accounts Version is set to: 13
2026-08-05 11:17:52:676 [ info nextcloud.gui.account.manager ./src/gui/accountmanager.cpp:196 ]: Migrate: restoreFromLegacySettings, checking settings group "Nextcloud"
2026-08-05 11:17:52:873 [ info nextcloud.sync.configfile ./src/libsync/configfile.cpp:732 ]: Default update channel is "daily" because of the current client build.
2026-08-05 11:17:52:972 [ warning nextcloud.gui.application ./src/gui/application.cpp:671 ]: Migration result: OCC::AccountManager::AccountsNotFound
2026-08-05 11:17:52:972 [ warning nextcloud.gui.application ./src/gui/application.cpp:673 ]: No accounts were migrated, prompting user to set up accounts and folders from scratch.
2026-08-05 11:17:53:041 [ info nextcloud.sync.clientproxy ./src/libsync/clientproxy.cpp:96 ]: Set proxy configuration to use the preferred system proxy for http tcp connections
2026-08-05 11:17:53:046 [ warning qt.core.qobject.connect unknown:0 ]: QObject::connect(QNetworkInformation, OCC::Application): invalid nullptr parameter
2026-08-05 11:17:53:048 [ info nextcloud.gui.application ./src/gui/owncloudgui.cpp:232 ]: No configured folders yet, starting setup wizard
2026-08-05 11:17:53:114 [ warning default unknown:0 ]: QQmlComponent: Component is not ready
As of 34.0.0 I can also see a small pop-up window outline. This is not readable as the box and contents (if any) are the same colour as the desktop background.
For me the same problem to disable starting the Nextcloud desktop client. Thanks for these commands. I used the Flatpak sysd manager and then graphically disabled the Nextcloud desktop.