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Every time Firefox starts, I receive error [JavaScript Application] error: de is null.What is this error?

  • 2 replies
  • 114 have this problem
  • 7 views
  • Last reply by armanys

armanys
armanys
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Every time Firefox starts I received a message:

[JavaScript Application] error: de is null


It may be because I installed few add-ons (including Greasemonkey scripts) or because of Java? I disabled add-ons (most of tem), but to no avail.

Every time Firefox starts I received a message: [JavaScript Application] error: de is null It may be because I installed few add-ons (including Greasemonkey scripts) or because of Java? I disabled add-ons (most of tem), but to no avail.

Chosen solution

Right, the problem was one of extensions installed. Problem solved!

Read this answer in context 👍 25

All Replies (2)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Start Firefox in Safe Mode to check if one of the extensions (Firefox/Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Firefox/Tools > Add-ons > Appearance).

  • Do NOT click the Reset button on the Safe Mode start window or otherwise make changes.
armanys
armanys Question owner
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Chosen Solution

Right, the problem was one of extensions installed. Problem solved!