1335379 - Hide Click-to-Activate dropdown for Flash during the Study

Status: RESOLVED WONTFIX

(Toolkit :: Add-ons Manager, defect)

Description

[:Felipe Gomes (needinfo for replies!)]

While we run the Flash study (bug 1335374), we don't want users to change this pref through the Add-ons Manager. Only users who had it at the default setting are eligible for the study, and to undo the change we want them to only have one avenue: quitting the study, which will then revert their pref.

Comment 1

[Robert Helmer [:rhelmer]]

(In reply to :Felipe Gomes (needinfo me!) from comment #0)
> While we run the Flash study (bug 1335374), we don't want users to change
> this pref through the Add-ons Manager. Only users who had it at the default
> setting are eligible for the study, and to undo the change we want them to
> only have one avenue: quitting the study, which will then revert their pref.

This makes sense. What can we do on the add-ons manager side to help?

Comment 2

[:Felipe Gomes (needinfo for replies!)]

The easiest would be if it could just check a pref value to hide the dropdown. That way, the Shield study add-on can just flip this pref instead of trying to access the guts of the Add-ons Manager to set something.

Comment 3

[:Felipe Gomes (needinfo for replies!)]

Rhelmer said he volunteers! :D

Comment 4

[David Durst [:ddurst]]

Rhelmer, I don't mean to pressure you, but relman said that they'd want this in by monday to keep it safely distanced from RC. Possible?

Comment 5

[:Felipe Gomes (needinfo for replies!)]

The pref to look for will be plugins.flashBlock.experiment.active == true

Comment 6

[Robert Helmer [:rhelmer]]

(In reply to :Felipe Gomes (needinfo me!) from comment #5)
> The pref to look for will be plugins.flashBlock.experiment.active == true

Hm. We probably don't want to put have about:addons check plugins.flashBlock.experiment.active pref though, do we? Seems like it should be a more generic pref if we do that.

However, it occurs to me that maybe we don't need a pref for this. Could you instead have your add-on add a pref observer? This seems to have the desired effect:

```
Services.prefs.addObserver(
  "plugin.state.flash",
  () => Services.prefs.setIntPref("plugin.state.flash", 2),
  false
);
```

Trying adding that observer then going to about:addons, the pref is immediately flipped back which the UI notices.

When your experiment is done you can simply remove the observer and the user will be back in control.

Comment 7

[:Felipe Gomes (needinfo for replies!)]

Summarizing the conversation on IRC:

The goal was not to simply force that the user don't change this setting (although we might use this snippet to do so because it's probably a good idea), but to hide the UI from the user altogether since we're designing the study to have a specific UI flow to participate.

However, having a one-off pref on the addons manager is weird, and handling reviews and uplifts for this would be overkill. So we'll do it through the add-on by injecting some CSS when about:addons load.