Kill It per als123

Modern browsers have largely conquered the problem of popup windows
being created by obnoxious web sites. Nowadays the bad guys have moved
on to what is called "slide-in" or "fly-in" advertising. There you
are reading an article and some ad starts sliding in from the side
to nag you to subscribe to something or other.

I had been using the venerable Remove It Permanently
(RIP) add-on for many years but it was not up to the job of removing slide-ins. This add-on is my replacement for RIP. It uses the latest Firefox add-on technology to be much more aggressive in rooting out this stuff.

Note: This is the Web Extension version. See the Release Notes for the features that have been lost.