1394789 - Tab previews in Windows Taskbar do not handle scaling of the website properly

Status: RESOLVED DUPLICATE of bug 1269810

(Core :: Widget: Win32, defect, P2)

Description

[Mertsch]

Attachment: 2017-08-29 15_03_47.png

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:56.0) Gecko/20100101 Firefox/56.0
Build ID: 20170825011442

Steps to reproduce:

* Enable option "Show tab previews in Windows Taskbar"
* Open any kind of site
* Increase the Zoom (to 300% for maximum effect)
* Hover over the taskbar, then over the site you zoomed in on


Actual results:

The Fx Window is filled with a Preview of the Tab that is scaled based on the size of the Window

if you choose 300% Zoom, then the tab preview is 1/3 of the total Window width
and the sites content again is 1/3 of the preview overlay

See attached screenshot


Expected results:

The preview window should render in a 1:1 scale as the site scaling is already applied before drawing the preview

Comment 1

[Robert Strong (they/them - no direct email)]

This is actually in widget code so changing component
https://dxr.mozilla.org/mozilla-central/source/widget/windows/WinTaskbar.cpp