1630994 - Decentraleyes adds one webRequest listener per tab, overwhelms request filtering in the main process

Status: RESOLVED FIXED

(WebExtensions :: Developer Outreach, task, P3)

Description

[Tomislav Jovanovic :zombie]

+++ This bug was initially created as a clone of Bug #1630737 +++

Originally reported here: https://www.reddit.com/r/firefox/comments/g2dett/firefox_75_slow_with_many_tabs_browser_issue_or/fnld9h7/

Here's a profile: https://perfht.ml/3a8E264

Here's the list of add-ons the user reports having:

    Privacy Badger
    ClearURLs
    FoxyTab
    Dark Background and Light Text
    Decentraleyes

Maybe related, see: https://gitlab.com/KevinRoebert/ClearUrls/-/issues/455

Specifically these STR:

Create new Firefox profile
Install the following addons (ClearUrls, Decentraleyes, Dark Background and Light Text, and Privacy Badger)
Hold Ctrl+T until 500+ new tabs are created. 
Visit Amazon.com & immediately try scrolling around, page will freeze/stutter for several seconds.
Disable/Remove any one of these four addons (ClearUrls, Decentraleyes, Privacy Badge, or Dark Background)
Visit/Refresh Amazon page again, scrolling will be smooth, no initial freeze/stutter.

and

Firefox option > General > Restore previous session
Exit Firefox
Relaunch Firefox to have all 500 tabs in suspended/unloaded state
Visit Amazon.com, page still freeze/stutter scrolling  for first few seconds.

Comment 1

[Tomislav Jovanovic :zombie]

This bug is specifically about reaching out to Decentraleyes authors, which should be doable since that's a recommended extension.
https://addons.mozilla.org/en-US/firefox/addon/decentraleyes/

(In reply to Andrew Swan [:aswan] from bug 1630737 comment #5)

Why is that a problem? Because decentraleyes adds a new onBeforeRequest listener for every tab that exists!! (https://git.synz.io/Synzvato/decentraleyes/-/blob/master/core/state-manager.js#L138-159).

• reach out to decentraleyes author and suggest reorganizing to use a single listener with dispatching code in the extension rather than creating a listener per tab

Comment 2

[Tomislav Jovanovic :zombie]

Hey Thomas, could you please take a look at this. Let me know if you have any questions or need any help!

Comment 3

[:Gijs (he/him)]

(In reply to Tomislav Jovanovic :zombie from comment #2)

Hey Thomas, could you please take a look at this. Let me know if you have any questions or need any help!

Did you mean to needinfo someone?

(Clearing perf whiteboard tags as this bug is about the add-on issue.)

Comment 4

[Tomislav Jovanovic :zombie]

I couldn't find Thomas on bugzilla, so I opened this bug for tracking and emailed him.

But apparently he has an account, so I'll also ni? here.

Comment 5

[Rob Wu [:robwu]]

I intend to fix the underlying Firefox issue in bug 1638007.

Comment 6

[Tim Spurway [:tspurway]]

S1 or S2 bugs need an assignee - could you find someone for this bug?

Comment 7

[Shane Caraveo (:mixedpuppy)]

This bug remains to validate the fix with external extensions.

Comment 8

[Rob Wu [:robwu]]

This issue should be resolved with bug 1631933 and bug 1638007, which is now in Firefox Beta (78).
Is there anyone on this bug who can verify that Firefox Beta performs better? Or do we need to ask QA?

Comment 9

[Rob Wu [:robwu]]

Firefox 78 is going to be released next week, with the above fixes. I don't see us doing any more work here, so I'll close the bug.