498821 - disable isOffScreenBrowser during pageloads

Status: RESOLVED WONTFIX

(Firefox for Android Graveyard :: General, defect)

Description

[Mark Finkle (:mfinkle) (use needinfo?)]

In bug 476186, we saw over 300ms Ts regression caused by setting isOffScreenBrowser too early in the startup path for the initial load. The theory was that setting the flag caused many events to be sent to the browser, slowing things down.

The fix for the Ts regression was to delay setting the flag until the first page was loaded.

Why not _always_ turn off the flag at the start of a pageload and set it at the end?

Comment 1

[Brian Crowder]

Isn't the whole point of ireflow that people can start viewing the page _as_ it loads, rather than waiting 'til it's totally loaded/reflowed?  Maybe I'm misunderstanding.

Comment 2

[Mark Finkle (:mfinkle) (use needinfo?)]

(In reply to comment #1)
> Isn't the whole point of ireflow that people can start viewing the page _as_ it
> loads, rather than waiting 'til it's totally loaded/reflowed?  Maybe I'm
> misunderstanding.

Yes, and tweaking isOffScreenBrowser won't affect that. But blassey poited out that isOffScreenBrowser could cause text input methods to fail, if users  begin to enter text during a pageload.

I tested this theory and soft keyboard is broken without isOffScreenBrowser=true

Comment 3

[Antonio Gomes (tonikitoo)]

mark, any tweak made to isOffScreenBrowser has been done already that could had affected bug 406837 ?

Comment 4

[Mark Finkle (:mfinkle) (use needinfo?)]

(In reply to comment #3)
> mark, any tweak made to isOffScreenBrowser has been done already that could had
> affected bug 406837 ?

Not to my knowledge. The example of loading google.com and making sure the textbox on the page gets focus - still works for me.

Comment 5

[Mark Finkle (:mfinkle) (use needinfo?)]

Not going to do this