1133234 - A vertical scrollbar often appears inside the hamburger menu if you click it right after Firefox launch

Status: RESOLVED DUPLICATE of bug 1088637

(Firefox :: Untriaged, defect)

Description

[Kostas]

Attachment: hamburger menu with vertical scrollbar.jpg

User Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:35.0) Gecko/20100101 Firefox/35.0
Build ID: 20150122214805

Steps to reproduce:

In a clean Firefox profile (I've noticed it in all Firefox versions, from 35.0.1 up to Nightly 38)
try to click the hamburger menu right after Firefox launch.


Actual results:

You might see a vertical scrollbar inside the hamburger (see the screenshot, it's from Nightly 38)
It doesn't happen every time but it does happen frequently.
This scrollbar appears only once/initially.
i.e. if you see such a scrollbar, then click outside the hamburger menu to close it, and then click the hamburger button again, the scrollbar will not appear.


Expected results:

The scrollbar should not appear.