1535656 - Quantum bar results flicker while typing a search

Status: VERIFIED FIXED

(Firefox :: Address Bar, defect, P2)

Description

[Alex Thayer [:alexical] (she/her)]

Right now, with browser.urlbar.quantumbar enabled, when typing out a search string, the results flicker in and out. This is unnecessarily noisy, and rather distracting. Compare to the same operation in Chrome, and with browser.urlbar.quantumbar off - the results do not get removed until new results are in.

Comment 1

[Dão Gottwald [:dao]]

from bug 1523602 comment 3:

Another detail that is not documented about the legacy urlbar: we distinguish results coming from the network from local results, because they have different characteristics.

For example, we put search suggestions before historical results, this means that every time the user types a new char, if remote results are slower to arrive, we'd end up adding historical results and then they would be pushed down by search suggestions, and this causes continuous flicker while typing.
What the old urlbar does is replacing same-type results, and once a search is done it removes the "stale" results that don't apply anymore. This prevents flicker of results, because before removing search suggestions the view waits for new ones to arrive (and often they may be the same already there).

This is implemented in UnifiedComplete in the legacy implementation, but in the Quantum Bar we can't reuse that, because the new API inserts new results one by one and lets the sorting to the muxer. Though, the view can likely do something like this using the result type/source.

This flicker prevention is probably more important than any resource saved by reusing elements.

Comment 3

[Dão Gottwald [:dao]]

Attachment: Bug 1535656 - Quantum bar results flicker while typing a search.

Comment 4

[Dão Gottwald [:dao]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=705943b429c8c34696ce008910dcbfe9c3373df3

Comment 5

[Mehmet]

Attachment: screencast.mov

Hello Dão. I also noticed a flicker in the Drop Down. Not sure if it is the same issue as mentioned in this report or if I should create a new report. I am attaching a screencast. Thanks in advance.

Comment 6

[Marco Bonardo [:mak] (Away Apr 25 - May 5)]

While reviewing the patch I discovered a couple problems with the way the controller sends out notifications to the view, that I'm looking into in bug 1548817. That bug is necessary to properly fix flickering here.

Comment 7

[Dão Gottwald [:dao]]

Marco has identified a blocker for this (bug 1548817) and should have a simpler patch here once that's resolved.

Comment 8

[Marco Bonardo [:mak] (Away Apr 25 - May 5)]

Attachment: Bug 1535656 - Quantum bar results flicker while typing a search. r=dao

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/d6756af10859
Quantum bar results flicker while typing a search. r=dao

Comment 10

[Oana Pop-Rus]

https://hg.mozilla.org/mozilla-central/rev/d6756af10859

Comment 11

[Cristian Comorasu, QA [:ccomorasu], Releae Desktop QA - Please contact [e-mail]]

I reproduced this issue using Fx 67.0a1 (2019-03-15) on Windows 10 x64.
I can confirm this issue is fixed, I verified using Fx 68.0b6 and Fx 69.0a1 (2019-06-03), on macOS 10.13.6, Windows 10 x64 and Ubuntu 16.04 LTS.