1426359 - Don't autofill/autocomplete and/or don't suggest on 404 and maybe other non-2xx errors

Status: NEW

(Firefox :: Address Bar, enhancement, P3)

Description

[eda]

User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0
Build ID: 20171206182557

Steps to reproduce:

I went to http://mysite/mypage and viewed it.  A few days later, I started typing in the location bar

    http://mysite/my

It suggested the completion 'page' and I pressed right-arrow to choose it.  Fine so far.  But now because of a change on the server the page has become 404.

So now I made a new tab and again started typing in the location bar

    http://mysite/my


Actual results:

Firefox still suggested the completion 'page' to give http://mysite/mypage, even though just a moment ago that page had returned a 404 result.


Expected results:

When a page gets 404 from the web server, Firefox should remember that it doesn't exist and no longer suggest it in the awesome bar.  (Or if it does appear as a suggestion, it should get a much lower priority and not be the autocompeted text you choose by pressing right-arrow.)

I wouldn't apply this to internal server errors, Forbidden, or other http status codes -- but where the server has just definitely told you the page does not exist, it makes sense not to suggest it again.

Bug 407760 seemed related to this, but either it has regressed, or wasn't fully fixed.  A comment there suggests filing a new bug, so I've done so.

Comment 1

[Marco Bonardo [:mak]]

The problem is that we cannot tell if the 404 is definitive or temporary, for example suppose that you visit a page while the maintainer is updating the website. It's clearly an edge case, but it could happen.
What we currently do is to not autocomplete pages that have always been a 404, and we also don't bump frecency of 404 pages, so it should, with time, fall quicker to lower frecency values.
We could probably be more aggressive, but it requires some brainstorming.

Comment 2

[eda]

>What we currently do is to not autocomplete pages that have always been a 404,

This could be tweaked to not autocomplete pages that were 404 on the most recent request.  They can still be shown in the suggestions so you can down-arrow to them if you want.

Comment 4

[Drew Willcoxon :adw]

Expanding the summary slightly to better capture bug 1626241 too (possible non 2xx statuses), and since comment 0 mentions both autofill and history results -- although it would probably be better to narrow this bug to autofill specifically and have a separate bug for history results. Also bumping up the priority since this deserves higher than P5 on second thought, at least to evaluate.