Join the Mozilla’s Test Days event from Dec 2–8 to test the new Firefox address bar on Firefox Beta 134 and get a chance to win Mozilla swag vouchers! 🎁

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Start page reads undefined.com instead of normal start page

  • 1 cavab
  • 3 have this problem
  • 1 view
  • Last reply by cor-el

more options

When opening Firefox the address shown is http://www.undefined.com/?uid=undefined&uc=undefined&ap=undefined&source=undefined&page=homepage&implementation_id=directions_0.0.2 and, instead of the Firefox home page there is a box that offers Indefinite Articles, Bellygraph, Stone Magic, Windward Road Runners, Picobusiness, Android Development or Laboratory. How do I get the Firefox home page to show and rid of these options?

When opening Firefox the address shown is http://www.undefined.com/?uid=undefined&uc=undefined&ap=undefined&source=undefined&page=homepage&implementation_id=directions_0.0.2 and, instead of the Firefox home page there is a box that offers Indefinite Articles, Bellygraph, Stone Magic, Windward Road Runners, Picobusiness, Android Development or Laboratory. How do I get the Firefox home page to show and rid of these options?

Chosen solution

You can check the target line in the Firefox desktop shortcut (right-click: Properties) to make sure that nothing is appended after the path to the Firefox program.

You can check the home page setting

  • Tools > Options > General > Startup: Home page

Firefox supports multiple home pages separated by '|' (pipe) symbols.


This issue can be caused by an extension that isn't working properly.

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: "3-bar" menu button/Tools > Add-ons > Appearance
  • Do NOT click the Reset button on the Safe Mode start window

You can use one of these to start Firefox in Safe Mode:

  • Windows: hold down the Shift key while starting Firefox
  • Mac: hold down the Options key while starting Firefox
  • Help > Restart with Add-ons Disabled
Read this answer in context 👍 0

All Replies (1)

more options

Seçilmiş Həll

You can check the target line in the Firefox desktop shortcut (right-click: Properties) to make sure that nothing is appended after the path to the Firefox program.

You can check the home page setting

  • Tools > Options > General > Startup: Home page

Firefox supports multiple home pages separated by '|' (pipe) symbols.


This issue can be caused by an extension that isn't working properly.

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: "3-bar" menu button/Tools > Add-ons > Appearance
  • Do NOT click the Reset button on the Safe Mode start window

You can use one of these to start Firefox in Safe Mode:

  • Windows: hold down the Shift key while starting Firefox
  • Mac: hold down the Options key while starting Firefox
  • Help > Restart with Add-ons Disabled