"Hide Caption Titlebar Plus" addon author here
The issue happens with new HCTP addon for Pale Moon (copy included here)
Browser also hangs on addon disable/uninstall (but a special alert message appears for choosing to avoid hanging)
For hanging, "Vertical Maximize" feature must be on (default in this copy)
The fact that it also hangs Firefox 43 may be a good clue to solve this.
In Firefox 52 thru 56 addon works ok.
Please let me know if I can be of further help in this!
Addon copy: Technical details:
Offending HCTP code already detected!: just look for "WhatIsHang.exe" in the code to see details, plus commented code to manually hang such a browser.
Also, there is a special flag to avoid hanging at all (affecting cleanup code):
In the js console put:
Code: Select all
Browser version: Pale Moon 27.5.1 (32bit), (also Firefox 43)
Installed extensions: "Hide Caption Titlebar Plus" (experimental copy 2) (included here)
(My original post about this, for reference)