This looks kinda janky, so I think we should avoid animating the root panel when we launch the app.

Patch has been waiting on review.

I found that when the settings app loads, document.location.hash == '#root', so we follow that path to show the panel. Since the HTML for the root panel is already loaded and showing, this isn't necessary. I find that this patch makes the settings app feel a lot smoother when it launches.

Comment on attachment 685347 [details] Link to https://github.com/mozilla-b2g/gaia/pull/6638 Sorry for the late review. Please let me finish working on my C2 bugs before reviewing this: I’m not sure this patch wouldn’t raise issues when the Settings app is launched on a different panel (web activities…).

As Chris just suggested, asking Evelyn to review this patch. Evelyn, please make sure this patch doesn’t raise issues when the Settings app is started on a non-#root URL (= web activities). Thanks!

This is a *0.7s* startup win for settings. 700 milliseconds.

I'm going to do the honors here ;). P1 because this is the most important startup win we have, along with bug 780692. Please let's get this reviewed and landed asap.

I've tested it and it works for the only one web activity we have now. It's a window disposition activity for wifi setting, starting at root page and then moving to wifi panel when the activity handler is invoked. so it's fine with the patch. I also made a inline disposition activity to test this patch, but it works not so good, the panel I specified for the inline activity will loading with a slip animation. My test case attached, you can test it by trigger an "Inline Activity Test" in UI Tests app.

Please note the old 'unlock' SIM PIN inline disposition activity which links to 'unlock_simpin.html' has been retired. That's why I say we only have a window disposition activity. So here, I'm testing a possible case of the future.

Comment on attachment 685347 [details] Link to https://github.com/mozilla-b2g/gaia/pull/6638 After a long discussion, Arthur has another approach for this issue that seems fix the issue and won't case web activity side-effect. So I'd like to left someone else review both patches and make a decision. :)

Evelyn, do we have an ETA concerning Arthur’s patch?

ooops, forget my last comment. /me needs more coffee

The idea of this patch is to apply the css animation after the target panel loaded and positioned. This solution also guarantees that the target panel not animated when the settings app is launched with a hash value.

Comment on attachment 688683 [details] Link to https://github.com/mozilla-b2g/gaia/pull/6817 r=me. Please squash all commit into one and remove the trailing white space before merging, thanks.

Fixed.

Just want to thank Margaret raised this issue and provided a patch which inspired Arthur so he can improve his approach. :) Also thank kaze and Tim's help on reviewing patch.

This was a nice bugmail thread to wake up to :) Thanks everyone for helping fix the issue!