I just did a reinstall of Ubuntu 17.10. On my previous installation that was an upgrade from 17.04, flash in Firefox worked fine.
After reinstalling, I installed Flash following the instructions at:
https://websiteforstudents.com/installing-the-latest-flash-player-on-ubuntu-17-10/
Now when trying to access sites using Flash I click on the icon to activate the plugin, click the button to give permissions and then nothing happens.
If I try with Chromium, Flash is not even recognised.
This is a major issue for me as two university courses I am taking require a working Flash plugin.
Any help would be very gratefully received.
OK. Fixed it.
First I uninstalled the plugins for both FF and Chrome; then reinstalled the FF plugin.
To make the plugin work I needed to open Herramientas --> Complementos (which I imagine is something like Tools --> Accessories in English), then select Plugins from the menu on the left.
Now click the Preferences button against Shockwave Flash.
Uncheck the checkbox against 'Bloquear contenido Flash peligroso o intrusivo' (Block dangerous or intrusive Flash content): and in the dropdown list at bottom right, select Activar Siempre (Always Activate - or whatever it is in English).
Flash now works, for me anyway.
Thanks
Peter