Text jumps after font size transition




5 years ago
5 years ago


(Reporter: Brian Victor, Unassigned)


21 Branch

Firefox Tracking Flags

(Not tracked)



(2 attachments)



5 years ago
User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:21.0) Gecko/20100101 Firefox/21.0 (Beta/Release)
Build ID: 20130511120803

Steps to reproduce:

I created an HTML document with a couple of lines of text, containing JavaScript that toggled a CSS class which in turn enabled a font size transition. A succinct example of this code is here: http://jsfiddle.net/RxW5B/1/

Actual results:

After the transition to the larger font size completes, the second line of text jumps noticeably.

Expected results:

The second line of text should have eased smoothly into its final location.

Comment 1

5 years ago
Created attachment 751452 [details]
Reporter's testcase

Comment 2

5 years ago
Could you test with Nightly, it seems to be fixed.
Flags: needinfo?(bugzilla)


5 years ago
Component: General → Layout

Comment 3

5 years ago
I still see the issue in nightly. The "Big text" jumps down about 30 pixels after smoothly growing, then jumps back up right before it starts shrinking again.

For anyone looking at the "Reporter's testcase" attachment (thanks for making it, Loic), it won't run from bugzilla in nightly due to a mixed content error. Downloading then running from the filesystem works fine.
Flags: needinfo?(bugzilla)

Comment 4

5 years ago
Incidentally, I'm also seeing "Big text" intermittently jumping during the transition. It appears to be jumping by the same proportion as the consistent final jump when this happens, then it returns to its normal path immediately.

I'm not sure if that's a separate issue or not, and either way I don't know how to reproduce it 100% of the time. But if you let my test case run for 30 seconds you're likely to witness it at least once.

Comment 5

5 years ago
I can reproduce the jumping if change zoom level of text only.

Steps to Reproduce:
1. Start Firefox with Clean profile
2. Open attachment 751452 [details]
3. Click "mixed-content-blocked-notification-icon" and Choose "Disable Protection on This Page" in dropdowm menu
4. Make sure "Zoom Text Only" mode, Alt > View > Zoom > Check "Zoom Text Only" 
5. Zoom out(Ctrl -) or Zoom in(Ctrl +)

Comment 6

5 years ago
And Reproduced in Firefox4 - Nightly24.0a1
Ever confirmed: true


5 years ago
OS: Mac OS X → All

Comment 7

5 years ago
Created attachment 751493 [details]
Test case without JavaScript

Test case without JavaScript. With "Zoom Text Only" enabled, zooming the page will demonstrate the problem.


5 years ago
Attachment #751493 - Attachment mime type: text/plain → text/html
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