1246245 - Webextensions and themes should also block e10s

Status: RESOLVED FIXED

(Firefox :: Extension Compatibility, defect)

Description

[Michelle Funches - QA]

1) Start Firefox with a clean profile
2) Access addons.mozilla.org and select and add-on from the Newest or Recently Added - Specifically select Wachete - Monitor website content changes Ver 1.3
3) Access about:addons and ensure Extensions displays the add-on you installed
4) Access about:config and add browser.tabs.remote.autostart.2 = true
5 In about:config add extensions.e10sBlocksEnabling = true
6) Restart Firefox
Expectation: 
A) browser.tabs.remote.autostart.2 = true
B) extensions.e10sBlockedByAddons = true
C) extensions.e10sBlocksEnabling = true 
D) Multiprocess windows in about:support is 0   [ 0/1 (default: false)]
Actual:
Multiprocess Windows         1/2 (default: true)
extensions.e10sBlockedByAddons = false
extensions.e10sBlocksEnabling = true

[Restart with Add-on Disabled]
1) Perform the steps to install Wachete
2) Access about:addons and ensure Extensions displays the add-on
3) Access about:support
4) Click the button Restart with Add-ons Disabled
5) Click Restart
6) Click Start in Safe Mode
Expectation:
A) browser.tabs.remote.autostart.2 = true
B) extensions.e10sBlockedByAddons = true
C) extensions.e10sBlocksEnabling = true 
D) Multiprocess Windows         0/1 (default: false)
E) Safe Mode         true
Actual:
Multiprocess Windows         2/2 (default: true)
extensions.e10sBlockedByAddons = false
extensions.e10sBlocksEnabling = true

This is occurring in 45.0b2 and 45.0b3
Platforms tested Windows 10, Windows 8.1, Windows 7, Windows XP, Ubuntu 14.04, Mac 10.11

Comment 1

[:Felipe Gomes (needinfo for replies!)]

Michelle, can you reproduce this issue while setting the pref in (5), before installing the add-on?

And did you try the same steps with other add-ons, and the issue here occurs with only this one?

Comment 2

[Michelle Funches - QA]

@Felipe: Correct. I can set the prefs "browser.tabs.remote.autostart.2 = true" and "extensions.e10sBlocksEnabling = true" and "extensions.e10sBlockedByAddons = false"
Next confirm the setting remain as input after a restart is a Pass.
Access about:addons and install the Wachete add-on.
The results are the same, Multiprocess remains enabled and the extensions.e10sBlockedByAddons remains false.
Also Yes: I have asked the testers to vary the add-ons daily, while a few add-ons remain constant we do vary the Collection, Recently Added,etc... So far this is the only one we have found that causes this anomaly.

Comment 3

[Jonathan Howard]

Probably all Web Extensions.

I just found first one listed that is a web extension under new (not knowing any or having found a better way to find one other than source examples.)
https://addons.mozilla.org/en-GB/firefox/addon/datascrapper

Only need to look at extensions.e10sBlockedByAddons, it updates live in about:config with restart-less extensions.

Comment 4

[:Felipe Gomes (needinfo for replies!)]

Ah, that's a very good catch! Thanks Michelle for reporting it and Jonathan for figuring it out. 

Michelle, that's expected. There's a class of add-ons that don't need to block e10s, and this is one of them. I don't know if there is a easy way to tell them apart, but I'll look into it

Comment 5

[:Felipe Gomes (needinfo for replies!)]

Ok, it was decided that these types of add-ons should also block the initial e10s rollout

Comment 6

[:Felipe Gomes (needinfo for replies!)]

Attachment: patch

Comment 7

[Dave Townsend [:mossop]]

Comment on attachment 8718335 [details] [diff] [review]
patch

Review of attachment 8718335 [details] [diff] [review]:
-----------------------------------------------------------------

Even more surprised we're doing this for themes too

Comment 8

[:Felipe Gomes (needinfo for replies!)]

Bill mentioned that one of the crashes that we saw in the first experiment, bug 1210099, is something that could be triggered by a webextension as well. So to reduce risk in the initial rollout, Blassey asked that only totally clean profiles would get it (and that's why I also included heavyweight themes).

Hopefully we'll lift the restriction, or parts of it, in the next version after shipping.

Comment 9

[Pulsebot]

https://hg.mozilla.org/integration/fx-team/rev/b16a5fa1a25e

Comment 10

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/b16a5fa1a25e

Comment 11

[:Felipe Gomes (needinfo for replies!)]

Comment on attachment 8718335 [details] [diff] [review]
patch

Approval Request Comment
[Feature/regressing bug #]: expands coverage of e10s block for add-ons of type "webextensions" and "themes"
[User impact if declined]: some users might not be blocked from the first e10s rollout
[Describe test coverage new/current, TreeHerder]: shipped on nightly, feature is covered by tests
[Risks and why]: very small, just expands the list of types in the code that is already in the tree
[String/UUID change made/needed]: none

Comment 12

[:Felipe Gomes (needinfo for replies!)]

[Tracking Requested - why for this release]: wanted for e10s on 46

Comment 13

[Liz Henry (:lizzard) (relman/hg->git project)]

Great, thanks. I was just about to ask about this from discussion on another bug.

Comment 14

[Liz Henry (:lizzard) (relman/hg->git project)]

Comment on attachment 8718335 [details] [diff] [review]
patch

This will slightly narrow the users we ship e10s to, to avoid crashes. 
Please uplift to aurora.

Comment 15

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/releases/mozilla-aurora/rev/042859215b0c

Comment 16

[Mayur Patil]

[bugday-20160323]

Status: RESOLVED,FIXED -> VERIFIED

Comments:
Test Successful

Component: 
Name			Firefox
Version			46.0b9
Build ID		20160322075646
Update Channel          beta
User Agent		Mozilla/5.0 (Windows NT 6.1; WOW64; rv:46.0) Gecko/20100101 Firefox/46.0
OS			Windows 7 SP1 x86_64

Expected Results: 
Yes

Actual Results: 
As expected