1420615 - Pressing ctrl key during inertial scrolling sometimes causes PDF reader to zoom

Status: RESOLVED DUPLICATE of bug 1503412

(Firefox :: PDF Viewer, defect, P3)

Description

[ben.s.kuhn]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:57.0) Gecko/20100101 Firefox/57.0
Build ID: 20171112125346

Steps to reproduce:

1. Open the following 2 tabs next to each other: https://en.wikipedia.org/wiki/Foobar, http://www.pdf995.com/samples/pdf.pdf

2. Focus the Wikipedia tab, then two-finger swipe vigorously downwards.

3. After releasing the trackpad but while the page is still scrolling from inertia, hold down "ctrl", then tap "tab" briefly to switch to the adjacent PDF.


Actual results:

After switching to the PDF tab, the PDF is rapidly zoomed out, presumably because it thinks I'm using the "ctrl+scroll wheel" shortcut for zooming out.


Expected results:

The PDF should not zoom out.

(As a bonus, it would be nice if ctrl/cmd+trackpad scrolling didn't cause zoom at all. If you want a trackpad gesture for zoom, it should be pinching, which currently does nothing on webpages. I frequently fat-finger cmd+scroll when switching between incremental search and scrolling, and never use it intentionally, nor is it a typical keyboard shortcut for Mac users afaik. But that's a different issue...)