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Flavours for Firefox 2.0 extension issues.



  • Allan Nyholm Nielsen

    I made a video of what I'm experiencing.

    Link is here 

    Let me know if what I'm doing is the wrong approach and what I really should do because nothing seems to work right.

  • Nuno

    Hi Allan!

    The issue you describe is in fact odd, and I didn't noticed earlier. Unfortunately, this is the Firefox behaviour. Please let me explain (sorry for being so descriptive):

    Firefox doesn't use native technologies for drawing (like Cocoa), instead, it uses a in-house developed technology called XUL, which is cross-plataform, but right from the start prevent the natural theming by the system. In order to allow theming of their windows, they provide two options: "complete themes" and "background themes" (previously known as Personas).

    Complete themes were very popular in the past, until Mozilla introduced this new Background Themes. Our v1.0 extension was a complete theme, and soon we got the disadvantages of it: poor, very poor performance; and because complete themes are built copying multiple files from the system (CSS, JS, etc), it was easily broken with Firefox updates. Complete themes allowed more customisation, but we had to drop it them because of several limitations (mostly performance).

    Background themes represent 99.9% of new Firefox themes, and are simple and fast. By design, Firefox determines when to check for theme updates (which doesn't fit Flavours needs). So Flavours shipped with a Extension and a Background theme. The extension refreshes new themes files on Firefox startup, and apply the Background theme right after. Since this Background theme is inexistent on filesystem (only in-memory), once disabled, you can only reenable it by disable/enable the extension (like you did), on restarting Firefox. The limitation of Background themes is that we can only change the background of the window (file spec) (more info).


    Now, the strange behaviour you are seeing is caused internally by Firefox. While developing the complete theme on v1.0, we noticed that the "Default" theme is in fact a Compete theme with a lot of C and CSS hacks and, some of the hacks directed to the background themes. So my guess here is that the buttons from the "Default" theme are being drawn by the system (as you see, they are drawn from the system Artfile), while the buttons from any Background theme (not just the Flavours one) are drawn separately by Firefox, with added transparency, so that they fit well with any Background theme.

    Unless Firefox extends the possibilities of Background themes, we are unable to theme better Firefox - I'm sorry!


    Hope this helps. Please let me know if I can be of further help!


    Happy theming,



  • Allan Nyholm Nielsen

    Thank you Nuno for that lengthy explanation. 

    It's a shame that a true implementation can't happen - perhaps in the future of Firefox.

    I did however found out that by using a different theme - one called Default Mod - that it now looks better like what I'm take a screenshot of.



    Screen Shot 2014-01-26 at 16.54.42.png

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