Update 2013.06.17: use Multiple Checkbox Checker.
Update 2012.12.10: also try CheckFox extension.
Update on 2011.12.01: the script doesn’t work for my FF8 anymore, looks like checkboxmate-lefedor-edition is a way to go now.
Upon installing WYSIWYG module in Drupal 7, site builder is presented with rather annoying task of selecting all the buttons to be enabled. The corresponding section of the WYSIWYG form – “buttons and plugins” is rather intimidating:
Site builder is required to go through all the checkboxes and check them manually. There is some ongoing work to fix the problem on Drupal side but meanwhile there is a better way – Firefox plugin! Install greasemonkey, restart your browser and add this user script.
The usage is not very straightforward at the beginning but it’s very handy once you get used to it. Position your mouse cursor above the first checkbox, click and drag with the mouse. All the checkboxes inside the rectangle you’ll draw will flip their state.