[Bug-librejs] "' " getting replaced with a newline causes annoyance in some forums

[onpon4]

On some forums, I believe those using Simple Machine Forums, such as
http://forum.uqm.stack.nl, LibreJS causes a problem when editing posts or
quoting posts where newlines are inserted. It seems, on inspection of the
page source, that these forums insert "'" at various places (at
seemingly regular intervals) in the textbox. LibreJS 4.9.2 replaces these
with newlines, causing the annoying effect.

I've seen other, similar problems caused by these changes by LibreJS; for
example, on https://www.thinkpenguin.com/gnu-linux/catalog, a link
specified as " / ", which normally results in going to
https://www.thinkpenguin.com/, is changed to "%20/%20", which causes the
link to break, and on that same page, a link with otherwise stripped
newlines has these newlines replaced with "%0A", breaking this link. Of
course, this is likely more of a problem with the website itself, but
regardless, LibreJS is causing some websites to break that would otherwise
work in the browser just fine without Javascript.

The problem only presents itself when scripts on the given page are
blocked. If all Javascript is allowed on the page, either temporarily or
via the whitelist, the problem goes away.