1394063 - Change <select> drop down to only request and display option list as options become visible.

Status: NEW

(Core :: Layout, enhancement, P3)

Description

[Neerja Pancholi[:neerja]]

See Bug 1118086 comment 74 for why we need this.

Comment 1

[Daniel Holbert [:dholbert]]

For reference, the testcase from Bug 1118086 (which also can serve as a testcase for this bug):
  https://bugzilla.mozilla.org/attachment.cgi?id=8833705

In current Nightly, if you click the <select> there, there are several seconds of jank before the menu appears. This bug is intended to eliminate that jank.

Comment 2

[favosys]

This issue is now breaking my site. Full info in a support case I created ( https://support.mozilla.org/en-US/questions/1175379 ) but in short I was updating an outdated page with a new look.

The current page (has the 1 sec delay issue):

http://www3.co.henrico.va.us/maps/subdivnamesearch.php

The new page with bootstrap (hangs and then crashes when you try to select a Street Name):

http://www3.co.henrico.va.us/mapstest/

Disabling e10s fixes the issue on both pages

Comment 3

[jscher2000]

With this approach, what will happen if the user clicks a select displaying 5000 options in alphabetical order and in the worst case scenario presses Z to jump to entries starting with that letter or presses the End key. Would that be where the delay is incurred, generating everything from A to Z? It still should be an improvement for more typical cases.

Comment 4

[Daniel Holbert [:dholbert]]

Dropping [qf] status, since this bug is in service of bug 1154677 which we're now taking a different strategy to fix (bug 1421229).

So: this whole bug may eventually be obsolete, once we've fixed bug 1154677.  For now I'll leave it open (in case we do decide to do something here),  but it's not QF.