I just tried this on a fully up to date install of Kubuntu focal 20.04, using the exact example link give in comment 3 and same firefox build.
Firefox successfully copied the repo clone link to the clipboard under KDE. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to firefox in Ubuntu. https://bugs.launchpad.net/bugs/1866900 Title: Javascript clipboard does not work Status in firefox package in Ubuntu: Incomplete Bug description: Pressing the "copy to clipboard" buttons on websites does not work. (e. g. Gitlab / Github) Manual ctrl-c is necessary. (Wrorks in several other browsers on same system) Snap / connection ? ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: firefox 74.0+build3-0ubuntu1 ProcVersionSignature: Ubuntu 5.4.0-18.22-generic 5.4.24 Uname: Linux 5.4.0-18-generic x86_64 NonfreeKernelModules: nvidia_modeset nvidia AddonCompatCheckDisabled: False ApportVersion: 2.20.11-0ubuntu20 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: anders 2056 F.... pulseaudio /dev/snd/controlC0: anders 2056 F.... pulseaudio BuildID: 20200309095159 Channel: Unavailable CurrentDesktop: ubuntu:GNOME Date: Tue Mar 10 19:45:10 2020 DefaultProfileExtensions: extensions.sqlite corrupt or missing DefaultProfileIncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite) DefaultProfileLocales: extensions.sqlite corrupt or missing DefaultProfilePrefErrors: Unexpected character ',' before close parenthesis @ /usr/lib/firefox/omni.ja:greprefs.js:729 DefaultProfilePrefSources: prefs.js DefaultProfileThemes: extensions.sqlite corrupt or missing ForcedLayersAccel: False InstallationDate: Installed on 2020-03-03 (6 days ago) InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Alpha amd64 (20200303) Profile0Extensions: extensions.sqlite corrupt or missing Profile0IncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite) Profile0Locales: extensions.sqlite corrupt or missing Profile0PrefErrors: Unexpected character ',' before close parenthesis @ /usr/lib/firefox/omni.ja:greprefs.js:729 Profile0PrefSources: prefs.js Profile0Themes: extensions.sqlite corrupt or missing Profiles: Profile1 (Default) - LastVersion=74.0/20200304223017 (Out of date) Profile0 - LastVersion=74.0/20200309095159 (In use) RunningIncompatibleAddons: False SourcePackage: firefox UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 07/24/2013 dmi.bios.vendor: LENOVO dmi.bios.version: I1KT24AUS dmi.board.vendor: LENOVO dmi.board.version: 31900003 STD dmi.chassis.type: 3 dmi.chassis.vendor: LENOVO dmi.modalias: dmi:bvnLENOVO:bvrI1KT24AUS:bd07/24/2013:svnLENOVO:pn10120:pvrIdeaCentreK450:rvnLENOVO:rn:rvr31900003STD:cvnLENOVO:ct3:cvr: dmi.product.family: IdeaCentre dmi.product.name: 10120 dmi.product.sku: LENOVO_MT_1012 dmi.product.version: IdeaCentre K450 dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1866900/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp