Bug 24177 – Full Page Zoom: Gmail gets horizontal scrollbar

• Component: Layout and Rendering
• Status: RESOLVED DUPLICATE

[Ojan Vafai]

cmd+ on gmail and you get a horizontal scrollbar. Each cmd+ makes the scrollWidth larger. This is probably some interaction between gmail's layout manager and the full page zoom. Same thing happens on Chrome and IE. However on Firefox you get a flash of a horizontal scrollbar, but then it resizes appropriately.

Will also follow up with gmail engineers.

[Ojan Vafai]

Created attachment 28243 [details]
Test case

Test case to help debugging what different browsers do. Seems that FF and WebKit scale the metrics they return off document.body and document.documentElement, but they do so in inconsistent ways and differently for quirsk v standards mode and top-level document v iframe.

[Ojan Vafai]

FF Standards and Quirks: Scales BODY and HTML elements in the top-level document, but not in iframes.

WebKit Standards: Scales the HTML in the iframe. Scales the BODY element in the top-level document.

WebKit Quirks: Scales the BODY in the iframe. Scales the HTML element in the top-level document.

IE Quirks: Only has metrics on the BODY and scales the BODY in the top-level document only.

IE Standards: Doesn't scale anything.

[Ojan Vafai]

Created attachment 28245 [details]
Now works in IE standards mode.

[Dave Hyatt]

The special cases of clientWidth and clientHeight in Element are not being adjusted for the document's zoom factor.  That's likely the bug.

I also noticed that all of the scrollLeft/Top/Width/Height getters and setters in HTMLBodyElement are not adjusting for full-page zoom either.

[Eric Seidel (no email)]

Created attachment 28247 [details]
standards mode test case (in Safari, this only works LOCALLY due to data: access permissions)

[Eric Seidel (no email)]

Created attachment 28248 [details]
quirks mode test case (same as standards, minus the doctype.  works in all browsers)

[Dave Hyatt]

Created attachment 28251 [details]
Patch for ojan/eseidel to try out

[Ojan Vafai]

With hyatt's patch, it fixes some of the Gmail/Reader bugs around scrollbars in FPZ. Hyatt pointed out on IRC that getBoundingClientRect doesn't take FPZ into account either. This likely is the remaining source of bugs for Gmail/Reader.

[Ojan Vafai]

Also, with hyatt's patch, WebKit now matches FF behavior in the attached tests cases for both quirks and standards modes.

[Jon@Chromium]

Can we get this patch submitted?  Where are we in the review process?

[Colm Buckley]

Any commentary on this?  Having a superfluous horizontal scrollbar in GMail really affects its usability and appearance.

        Colm

[Colm Buckley]

Hm; I notice that this patch *does* seem to be in place in the latest WebKit source.  The current binary download (r42583), though, still exhibits the horizontal scrollbar behaviour in GMail.  Is there a separate issue, or is this patch not included in the binary releases?

    Colm

[Colm Buckley]

Looks like a separate issue; the persistent horizontal scrollbar only appears when "right side chat" is enabled in GMail.  I will investigate further.

[Erik Arvidsson]

Gmail also uses getBoundingClientRect which is not working correctly when zoomed. Test case coming up.

[Erik Arvidsson]

Created attachment 30056 [details]
Testcase showing that getBoundingClientRect is not working correctly when zoomed

Try to zoom on the page. All numbers should be 100 at all times (unless you scroll the page).

[Eric Seidel (no email)]

Looks like this was fixed by bug 25750.  Marking as a dupe.

*** This bug has been marked as a duplicate of 25750 ***