Rated 5 out of 5 stars

deur Firefox user d0919a op Des. 1, 2017 ·

found a modified version of the Custom Buttons extension that works in SeaMonkey 2.49.1

download it from this forum: http://custombuttons.sourceforge.net/forum/viewtopic.php?f=5&t=3743

This user has a previous review of this add-on.