Hi kkapsner. Thanks. Version 0.1.3 indeed works on FF28. Maybe a FF bug caused it to offer updating to v0.2 after updating to FF28. Right now it only offers updating to 0.1.6, which is the latest that indicates (incorrectly?) FF28 as supported.
And thanks for the extension! Now I just need something to block/control CSS transitions... :)
And also thanks for pointing out, indirectly, that it's possible to download older versions from the Mozilla site :) (hidden at the bottom on the page, under the misleading title "Version Information", then "See complete version history". There's also more info there on supported FF versions per extension version).
I'll use Github in the future (*sigh* another something that needs an account...).
I'm on FF v28. The extension carried over from a previous FF version, and I also updated it after moving to v28. In FF's settings it's not disabled due to being "incompatible". Yet, in the FF addons site it says it's incompatible with v28.
Assuming it's supposed to just block Canvas elements (which is what I'm after; fingerprinting is a secondary concern which I wasn't aware of before), I don't see any blocking action. The same was true also with the previous FF version I was using: no blocking. I was able to install it to begin with, so I think it should have worked, but maybe I'm missing something.
Version 0.2.0 is definately not working with FF 28. Try an older version (I would start with 0.1.6 and then go backwards). If you realy want to have blocking of the canvas you have to set the blocking mode to "block all".
PS: If you have further problems and want to contact me, please use github: https://github.com/kkapsner/CanvasBlocker/issues .