1724972 - Address bar sometimes only updates partially after input, with full update delayed

Status: RESOLVED INVALID

(Firefox :: Address Bar, defect, P5)

Description

[Yorwba]

Attachment: Screen recording demonstrating the problem

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:90.0) Gecko/20100101 Firefox/90.0

Steps to reproduce:

1. Make Firefox run slow like molasses. (Makes it easier to get 100% reproducibility. You can also try typing quickly.)
2. Have DuckDuckGo as the main search engine.
3. Have a search bookmark with keyword "duden" and URL "https://www.duden.de/suchen/dudenonline/%s".
4. Type "duden sodass" into the search bar and hit enter.

Actual results:

1. Before the word "duden" is completed, the suggestion to search with DuckDuckGo is displayed.
2. Once the word is completed, the suggestion to search with DuckDuckGo briefly remains.
3. A bookmark star is added to the DuckDuckGo logo and the text of the suggestion changes to https://www.duden.de/suchen/dudenonline/, with the two occurrences of "duden" highlighted in bold. The text that follows still says "Search with DuckDuckGo".
4. "Search with DuckDuckGo" changes to "Visit", but the DuckDuckGo logo remains.
5. After completing "duden so", the suggestion reverts to searching for "duden so" with DuckDuckGo.
6. After completing "duden soda", the suggestion is now to search for "duden soda" with DuckDuckGo.
7. A bookmark star is added to the DuckDuckGo logo and the suggestion changes to "www.duden.de: soda", with "duden" and "soda" highlighted in bold. Neither "Search with DuckDuckGo" nor "Visit" is displayed at the end.
8. After completing "duden sodass", the DuckDuckGo logo changes to the Duden logo, and the suggestion changes to "www.duden.de: sodas" (note only one 's' at the end), with "duden" and "sodas" highlighted in bold.
9. After hitting enter at this point, the page "https://www.duden.de/suchen/dudenonline/sodas" (note only one 's' at the end) is loaded.

(Under normal operating conditions (i.e. Firefox running only regularly slow) the partial updates and unnecessary switching between search engines lead to noticeable flicker. Submitting a partial search because I hit enter in the window of time between entering my search string and having it processed by the search suggestion system happens a lot to me.)

Expected results:

The highlighted suggestion should update in sync with the input.
Once a search keyword is completely typed, all following input should be treated as input for the corresponding search engine.
The displayed information should be consistent at all times.
Hitting enter after entering a search string should include the whole input in the resulting search.

Comment 1

[Yorwba]

Attachment: Frame corresponding to step 1

Comment 2

[Yorwba]

Attachment: Frame corresponding to step 2

Comment 3

[Yorwba]

Attachment: Frame corresponding to step 3

Comment 4

[Yorwba]

Attachment: Frame corresponding to step 4

Comment 5

[Yorwba]

Attachment: Frame corresponding to step 5

Comment 6

[Yorwba]

Attachment: Frame corresponding to step 6

Comment 7

[Yorwba]

Attachment: Frame corresponding to step 7

Comment 8

[Yorwba]

Attachment: Frame corresponding to step 8

Comment 9

[Yorwba]

Attachment: Frame corresponding to step 9

Comment 10

[Yorwba]

The attached still frames were extracted from the recording using

ffmpeg -i search_bar_bug_cut.mp4 -vf "select='gt(scene,0.001)'" -vsync vfr search_bar_bug_images/img%d.png

and then I picked 9 images (out of 21) that showed something interesting going on.

Comment 11

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Firefox::Search' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Comment 12

[Drew Willcoxon :adw]

A few things here:

There's a lot of room for improvement WRT to flickering for sure. We have several open bugs on it.

Re: typing fast, room for improvement there too. Our current architecture is pretty racey. We fetch results and show them as they're ready, and if the fallback search result happens to come in before the keyword result and you hit enter, then we'll do a fallback search. Bug 1724481 is about this.

Your video is extremely bad though and is more than just flicker (obviously). Was the rest of your system running that slowly, or was Firefox an outlier?

Comment 13

[Yorwba]

The slowness was intentional. After hitting enter too quickly and ending up searching for the wrong thing for the umpteenth time, I finally decided to make a screen recording, but then I couldn't reproduce it anymore. So I used a Python script to allocate a lot of memory and push Firefox into swap.

I do sometimes get slowdowns that make typing in the address bar more likely to go wrong, but those are even harder to reproduce.

If everything here is already covered in other bug reports, this one can be closed as a duplicate, I guess.