1327864 - Livestream comments on Youtube: sometimes blue button "Show more comments" teleports to the top and back

Status: RESOLVED WORKSFORME

(Core :: General, defect)

Description

[arni2033]

>>>   My Info:   Win7_64, Nightly 49, 32bit, ID 20160526082509
STR_1:
1. Extract attached "testcase 1" into a folder with short full name, open the .htm file
2. Scroll the box with comments to the beginning
3. Hover mouse over the blue button "show more comments", move mouse above that button,
   then below that button
4. Repeat Step 4 several times

AR:  The blue button sometimes teleports to the top of comments box and back
ER:  No twitching

Comment 1

[arni2033]

Attachment: testcase 1 - Livestream comments on Youtube comments - testcase 1.zip

Comment 2

[arni2033]

>>>   My Info:   Win7_64, Nightly 53, 32bit, ID 20161229030206 (2016-12-29)
Reproducible
I reproduced this in the 1st try somehow. The mouse movement should be continuous, e.g. at least 10 seconds. Step 4 should refer to Step 3. I'll attach screencast after 1 month probably,
when I'll have time. Maybe HWA is involved, but again, no time.

The notification twitchies even if JavaScript is disabled. I assume it happens
only if some animations are present on the page.

Comment 3

[Justin [:JW_SoftvisionQA]]

I can not reproduce this issue on the latest nightly  	Mozilla/5.0 (Windows NT 6.3; WOW64; rv:54.0) Gecko/20100101 Firefox/54.0

As the button does not twitch.

Comment 4

[Firefox Bug Husbandry Bot]

Moving from Core::Untriaged to Core::General https://bugzilla.mozilla.org/show_bug.cgi?id=1407598