Does not work well on Cinnamon desktop. This Flatpak version may be for KDE. App runs but right-clicking on icon in notification area > Open Nextcloud Desktop does nothing. So impossible to add new server. Right click > Nextcloud Settings shows under Info, near the bottom: "Nextcloud Desktop Client Version 33.0.7daily (KDE running on xcb)". Please provide a Nextcloud client that works on Mint Cinnamon. Thanks.
Installed on new Mint 21.2 install without issue. Flatpak is convenient as it updates automatically, although generally a couple days behind the AppImage on nextcloud.org. Note must be manually added to "Startup Applications" after first install.
When I realized that the version in the software center was the actual version of the app, I installed it instead of the AppImage. Seems to work fine. I had to add the "Nextcloud Client" to the "start programmes" manually, though. Seems to work fine now! Therefore, I'll rate it 5 stars. I am using Linux Mint 21.1 (Vera) Cinnamon Edition.
I do like the app. But I always have issues with auto-start the app during startup. It never works. Even if I check the checkbox in the settings, to start during the boot.