Opened on 05/08/2017 at 05:16:37 PM

Closed on 05/09/2017 at 12:57:07 PM

Last modified on 05/16/2017 at 01:16:57 PM

#5222 closed defect (fixed)

ABP/FF 2.9 devbuild doesn't install properly on older Firefox versions

Reported by: rscott Assignee: trev
Priority: P1 Milestone: Adblock-Plus-2.9-for-Firefox
Module: Adblock-Plus-for-Firefox Keywords:
Cc: Blocked By:
Blocking: Platform: Firefox
Ready: yes Confidential: no
Tester: Ross Verified working: yes
Review URL(s):

Description (last modified by trev)


Platform: Windows 8.1 32-bit/ Firefox 45.9.0 ESR
ABP/FF build:


  1. On a fresh install of FF 45.9.0, install the current ABP/FF 2.9 candidate build from the development-builds page. (Click the link to the current devbuild XPI, Allow, Install.)
  2. Observe: Firefox reports that ABP was installed successfully. However, the ABP first-run page does not appear.
  3. From the Firefox hamburger menu, click Add-ons > Extensions > Adblock Plus - Options.
  4. Observe: The options page text has ampersands (&) strewn throughout -- see screenshot.
  5. Click the "Filter preferences…" button. Observe: the Filter preferences window does not open.

Expected behaviour

  • Either the ABP extension installs as normal (first run page appears; no text errors; Filter preferences window is usable), or
  • If future versions of ABP/FF cannot be made to work on older versions of Firefox, users should be prevented from installing them or upgrading to them.

Further details

  • The same behaviour was observed after upgrading an existing ABP/FF install (2.8.2 to on the same platform (FF 45.9.0 on Win8.1/32bit).
  • Browser Console shows the following message:

Exception running bootstrap method startup on {d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d}: TypeError: params.webExtension is undefined

What to change

Embedded WebExtensions are only supported starting with Firefox 51. We have to adjust compatibility info accordingly so that installing in older Firefox versions isn't possible.

Attachments (1)

win8.1-ff45esr-options-page-postinstall.png (122.6 KB) - added by rscott on 05/08/2017 at 05:17:39 PM.
ABP 2.9-devbuild options page immediately post-install

Download all attachments as: .zip

Change History (11)

Changed on 05/08/2017 at 05:17:39 PM by rscott

ABP 2.9-devbuild options page immediately post-install

comment:1 Changed on 05/08/2017 at 06:33:32 PM by traynard

Seeing same behavior on FF50 on mac and windows.

comment:2 Changed on 05/09/2017 at 06:58:34 AM by rscott

  • Summary changed from ABF/FF 2.9 devbuild doesn't install properly on older Firefox versions to ABP/FF 2.9 devbuild doesn't install properly on older Firefox versions

comment:3 Changed on 05/09/2017 at 07:03:58 AM by rscott

For clarity, the current ABP/FF devbuild ( does seem to install and work correctly on FF51/Win 8.1. So it looks as though the changes between Firefox 50 and 51 might be involved in this issue.

comment:4 Changed on 05/09/2017 at 12:16:56 PM by trev

  • Description modified (diff)
  • Owner set to trev
  • Priority changed from Unknown to P1
  • Ready set

comment:5 Changed on 05/09/2017 at 12:21:56 PM by trev

  • Review URL(s) modified (diff)
  • Status changed from new to reviewing

comment:6 Changed on 05/09/2017 at 12:53:56 PM by abpbot

A commit referencing this issue has landed:
Issue 5222 - Drop support for Firefox 50 and older

comment:7 Changed on 05/09/2017 at 12:57:07 PM by trev

  • Resolution set to fixed
  • Status changed from reviewing to closed

comment:8 Changed on 05/09/2017 at 12:59:39 PM by rscott

  • Milestone Adblock-Plus-2.9-for-Firefox deleted

comment:9 Changed on 05/09/2017 at 01:01:29 PM by trev

  • Milestone set to Adblock-Plus-2.9-for-Firefox

comment:10 Changed on 05/16/2017 at 01:16:57 PM by Ross

  • Tester changed from Unknown to Ross
  • Verified working set

Extension is now marked as incompatible with FF < 51 on the Mozilla Addons page.

Firefox 50 / Windows 7

Add Comment

Modify Ticket

Change Properties
as closed .
The resolution will be deleted. Next status will be 'reopened'.
to The owner will be changed from trev.
Note: See TracTickets for help on using tickets.