It works for me. Why not download a separate new version to a folder and give it a try.

https://www.mozilla.org/en-US/firefox/all/#product-desktop-release

Operating System: openSUSE Tumbleweed 20210106 KDE Plasma Version: 5.20.4 KDE Frameworks Version: 5.77.0 Qt Version: 5.15.2 Kernel Version: 5.10.4-1-default OS Type: 64-bit Processors: 8 × Intel® Core™ i7-4810MQ CPU @ 2.80GHz Memory: 31.0 GiB of RAM Graphics Processor: Mesa DRI Intel® HD Graphics 4600

Hi, jonzn4SUSE

Thanks for you reply! That seems to be a solution. Maybe I should't persist in finding the reason why the shortcut doesn't work.

On Linux you use and always had to use "Ctrl+Shift+O" (letter 'o') to open the Library. On Linux this has never been "Ctrl+Shift+B", but in the next release (85) "Ctrl+Shift+B" will toggle the Bookmarks Toolbar.

Hi, cor-el

What? I thought it was ok when I saw my version verified the firefox support (see the screenshot below)

So i was mislead by https://support.mozilla.org/en-US/kb/keyboard-shortcuts-perform-firefox-tasks-quickly

I checked that my desktop environment GNOME 3 and "ctrl+shift+B" was not used.

Works for me in Firefox 84 on Linux. Screenshot of the Browser Toolbox.