Hello everyone, I have been trying something for both Iceweasel and Epiphany, and the results were different !!

It's about the adobe flash plugin file "libflashplayer.so" : after downloading it, it(a hard link) was in the desktop, and I preferred making symlinks rather than copying the file to the plugin directory:

-for Epiphany, I made this symbolic link: "ln -s /home/....file.so /usr/lib/epiphany-gecko/2.22/extensions/file.so" (in extensions directory)
and this one: "ln -s /home/....file.so /usr/lib/epiphany-gecko/2.22/plugins/file.so" (in plugins directory)

and the flash videos worked right after that !!

Now,I removed the symlink located in the extensions directory, to get sure which directory I should from now on put the plugins in .. I verified, but found that flash videos still were working !
I guessed at first that plugins directory was the one !
I removed the symlink from it to get sure for 100 % (removed from plugins too)
However, flash videos still worked !!

PS: I did exactly the same thing for Iceweasel, and it showed that removing from /usr/lib/mozilla/plugins makes flashes work no more

Thanks a lot, and sorry for the length.

did you restart epiphany afterward? you can use lsof to see where epiphany is loading the plugin from since it'll be an open file.

well, first of all, thanks for the time you spent reading this long story of mine..and guess what, I have news..I was thinking to myself, maybe epiphany figured out the path of the hardlink now, and it's reading it directly without having to get through the symlink I created and then removed. So, I tried moving the file somewhere else with the command "mv -ivT ..."
results: Flashes work no more in epiphany !!!!

I then moved the file back where it was, and checked out in epiphany : the flashes were working again !!!!

Well good idea, even though I didn't do it, it would've helped, thanks.