Hi,
we approved
https://bugzilla.mozilla.org/show_bug.cgi?id=920803 to land
on both aurora and beta.
The width of the blocked-plugin popup was hard-coded, and it's now
exposed to l10n.
If you find that the blocked-plugin UI needs adjustment of size, please
revisit this string.
If not, ignore the string, the build will add the en-US value and you'll
be just fine and with the same functionality as before.
Axel