Snippets code from my daily experience

December 20, 2007

Firefox 3 and broken extensions

When I started Richscrollbar (RSB for friends) development I could not figure out a so difficult programming life cycle.

After all its task is simple, add extra buttons to browser scrollbars to speedup movements inside web page.

Gecko is affect by a bug that reduces RSB productivity dramatically but I’ve created it anyway.

Now I discover RSB totally doesn’t work with Firefox 3 beta 2, Mozilla guys changed API and I suspect introduced some regression.

Obviously it is impossibile to explain the problem to Mozilla, they are so busy to fight against the world.

After some frustrating debug I found the problems and fixed them.

Problem nr 1.

The nsIStyleSheetService.USER_AGENT has changed behaviour without documenting it (at least at this date)

I used USER_SHEET in Firefox 2 but under FF3 the same code simply doesn’t work.

I’ve replaced it with the other flag AGENT_SHEET and magically RSB started to work.

Where can I read the new behaviour? Damned Mozilla 😛

Problem nr 2.

An horizontal useless scrollbar is always visible only on tab window open at browser startup, if user opens new tab and/or windows this dumb doesn’t appear, sigh!

I found a reasonable workaround hiding the scrollbar inside the notificationbox component.

I hope to publish the fixed RSB on this weekend.



  1. you may be interested in this but: needless to say, moz dev credibility has dropped a few notches. this sort of behavior wouldn’t be allowed in a real software house.

    Comment by alta88 — March 30, 2008 @ 5:01 pm

  2. I agree with you, behind “security” Mozilla does what it wants irrespective extension developers works.
    My Richscrollbar is definitively dead, read here

    Comment by dafi — March 30, 2008 @ 5:09 pm

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