Adobe Flash Player has officially stopped working, since apparently Adobe included a logic bomb a few releases back with an expiry date in it <https://www.theregister.com/2021/01/12/flash_is_dead/>. However, for those who really, really need it, this article <https://charleswilkinson.co.uk/2021/01/12/how-to-use-flash-in-2021/> describes a workaround to re-enable it for certain sites (e.g. corporate intranet ones), by editing certain .cfg files. Those .cfg files don’t exist on a Linux installation -- not by default, anyway. However, doing a “strings” on libflashplayer.so finds (among other things) a reference to “/etc/adobe” and “/opt/adobe” directories. So perhaps you could create one of these and put files with the right names in it? Anyway, I’m just throwing this out there for anyone who wants to play with it. ;)