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On Firefox beta startup I get a javascript error before the browser opens: what happened:TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined. The browser pane then remains empty until manual refresh.

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  • Last reply by rjohnson19

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Every time starting Firefox beta (4.0b1) I get a javascript application popup error saying "what happened:TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined" before the browser opens. Clicking OK closes popup, browser opens to empty page (incorrect). Browser refresh reveals expected content.

This happened

Every time Firefox opened

== I installed beta firefox on Windows Vista system.

Every time starting Firefox beta (4.0b1) I get a javascript application popup error saying "what happened:TypeError: Components.classes['@mozilla.org/extensions/manager;1'] is undefined" before the browser opens. Clicking OK closes popup, browser opens to empty page (incorrect). Browser refresh reveals expected content. == This happened == Every time Firefox opened == I installed beta firefox on Windows Vista system.

Chosen solution

Carl,

The first message is due to an extension that is not compatible with Firefox 4.0 beta 1.

Did you turn compatibility checking off or use the add-on compatibility reporter? Try disabling extensions that are indicating incompatibility in Tools -> Add-ons.

It may be the Ask Toolbar (AskTbTRL/3.8.0.12304 in user agent), try disabling that.

Otherwise you will have to disable all add-ons and re-enable one by one until the problem appears, and you identify the problematic extension. See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

Your second issue may be covered by this bug: https://bugzilla.mozilla.org/show_bug.cgi?id=575281 or it may be due to the incompatible extension(s).

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Chosen Solution

Carl,

The first message is due to an extension that is not compatible with Firefox 4.0 beta 1.

Did you turn compatibility checking off or use the add-on compatibility reporter? Try disabling extensions that are indicating incompatibility in Tools -> Add-ons.

It may be the Ask Toolbar (AskTbTRL/3.8.0.12304 in user agent), try disabling that.

Otherwise you will have to disable all add-ons and re-enable one by one until the problem appears, and you identify the problematic extension. See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

Your second issue may be covered by this bug: https://bugzilla.mozilla.org/show_bug.cgi?id=575281 or it may be due to the incompatible extension(s).