The Firefox 56 package was running very fast lately, but since mozilla-firefox-56.0-x86_64-2 the browser keeps locking up and freezing to the point my desktop environment says the window is not responding very often.

I have tried to reset my mozilla profile folder, safe-mode etc, but still locks up often.

The only changes in the package rebuild i see are;
I ended up removing the slackware package, and downloading firefox from their own site, this version works fine from the tarball?

Just wondering if anyone else was getting the same problems, as i don't understand why accessibility options would cause the browser to lock up constantly.

I'm running Firefox 56 on two Slackware64-current units and all is well.

Hardware acceleration in Firefox can sometimes cause some odd issues, perhaps try disabling this?

Anyway I assume that the pre-built version from Mozilla does have accessibility enabled.

Just an assumption, didn't check (running 52.4.0, not 56)

I reverted to Firefox version 55.0.3 due to some issues with v.56 (problems with plugin +).