Bug 39924

Summary: Reducing page zoom causes incorrect component offset values
Product: WebKit Reporter: Andre-John Mas <andrejohn.mas>
Component: Layout and RenderingAssignee: Nobody <webkit-unassigned>
Severity: Normal CC: ahmad.saleem792, eae, leviw, mmacleod, rniwa, simon.fraser, zalan
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Mac (Intel)   
OS: OS X 10.6   
Bug Depends on: 60318    
Bug Blocks:    
Description Flags
Test case illustrating the bug none

Description Andre-John Mas 2010-05-29 11:40:22 PDT
Created attachment 57414 [details]
Test case illustrating the bug

I have run into an issue where zooming out of a page ( cmd - ) causes the element offset to become incorrect. This can have an impact on dynamic HTML which is not expecting this behaviour. Tests indicate this is a WebKit related issue, since both Safari and Chrome are impacted, while Opera and Firefox are not.

Tested on MacOS X 10.6 only.

I have attached a test case showing the issue:
  1 - open the test case
  2 - click on the button, in page, and observe displayed offset in console
  3 - zoom out at least twice (more if possible)
  4 - click on the button, in page, and observe displayed offset in console, compare to step 2
Comment 1 Andre-John Mas 2010-06-01 17:04:54 PDT
Just for reference versions of browsers tested with:
  - Google Chrome (OS X) 5.0.375.55
  - Webkit 4.0.5 (6531.22.7, r58136)
  - Firefox 3.6.4
  - Opera 0.10
Comment 2 Andre-John Mas 2010-06-01 17:05:12 PDT
Oops, that should have been 10.10 for Opera
Comment 3 Emil A Eklund 2011-06-24 11:10:53 PDT
*** Bug 63333 has been marked as a duplicate of this bug. ***
Comment 4 Ahmad Saleem 2023-05-05 12:56:20 PDT
I am not able to reproduce this bug using steps from Comment 0 and also using the attached testcase on Safari 16.4 and it does not show different values (I zoomed in to extreme as well - more than once).

It matches with Chrome Canary and keep it as:

[Log] left: 300, top: 300 (attachment.cgi, line 27, x6)

Comment 5 Andre-John Mas 2023-05-05 13:14:36 PDT
I just tested using Safari on iOS 16.4.1 (a) and I can no longer reproduce the issue. 

I’ll close this.