808802 - xul panels displayed by addons are incorrectly scaled on non-HiDPI secondary screen

Status: RESOLVED DUPLICATE of bug 822266

(Core :: Widget: Cocoa, defect)

Description

[Jonathan Kew [:jfkthame]]

STR, using a Retina MacBook Pro with a non-HiDPI secondary display attached:

1. Install the Mozilla Reps Companion add-on, and enable the add-ons bar.

2. With the browser window on the primary screen (built-in Retina display), click the Moz Reps Companion icon in the add-on bar to display the add-on's panel. Note that it displays fine, modulo bug 803383.

3. Drag the browser window across to the secondary (non-Retina) display.

4. Again, click the Moz Reps Companion icon to display the panel. Note that although the panel is the right size, its content is grossly oversized (incorrectly scaled).

(This is not unique to the Mozilla Reps Companion add-on; a similar issue was observed with the tos;dr add-on prior to the landing of bug 803068, which prevents it displaying any panel content.)

If the non-HiDPI screen is the system's primary display, and the add-on's panel is displayed on the secondary HiDPI screen, the inverse problem will appear: the panel content is scaled to half the proper size.

Comment 1

[Jonathan Kew [:jfkthame]]

BTW, this problem does *not* affect the "flyout" panels displayed by the Social API feature.

Comment 2

[Jonathan Kew [:jfkthame]]

This is fixed in Nightly as of 2013-02-04, by the landing of bug 822266. Which makes sense, as what's happening here is that content is suddenly finding itself on a different-resolution screen, but didn't go through the kind of widget-move that would have fired a BackingScaleFactorChanged from the widget level.