Flash works only when that checkbox is disabled STEPS TO REPRODUCE 1. Check the box 2. Go to a website that uses flash (for example https://get.adobe.com/flashplayer/about/) OBSERVED RESULT Instead of the flash content I see the error message "Plugin could not be loaded". If I go back and uncheck it the flash content loads again. EXPECTED RESULT SOFTWARE/OS VERSIONS Operating System: Gentoo Linux KDE Plasma Version: 5.16.0 KDE Frameworks Version: 5.59.0 Qt Version: 5.12.3 Kernel Version: 5.1.7-gentoo OS Type: 64-bit Processors: 16 × AMD Ryzen 7 2700 Eight-Core Processor Memory: 62,9 GiB ADDITIONAL INFORMATION This used to work fine in Falkon 3.0
I've tested this and can confirm. However flash is EOL (End of Life) as of December 31 this year.
Turns out there was a problem with my flash plugin and when the checkbox was disabled it falled back to HTML5.