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TypeError messagebox[0] is unidentified comes up opening Gmail. Any solution to removing it, annoying.

  • 2 replies
  • 6 have this problem
  • 2 views
  • Last reply by cor-el

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Open firefox, open Gmail and a box with, TypeError messagebox[0] is unidentified, opens. Have to click x to shut and a second box that opens. This happens every time opening Gmail.

Open firefox, open Gmail and a box with, TypeError messagebox[0] is unidentified, opens. Have to click x to shut and a second box that opens. This happens every time opening Gmail.

All Replies (2)

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Don't know about the messagebox[0] error but it could possibly be related to the following problem which has come up several times today. Can you actually see your emails in your inbox, or have you just been writing emails so far today. Try Googling the exact message and paste it here before solving to help others later find solutions based on exact message wording when you or someone else does solve problem.

GMail entire message content missing (blank) after header title

In Firefox, if you have "Adblock Plus" extension.

  1. "Ctrl+Shift+F" Preferences (or right click on ADP symbol, and choose preferences)
  2. 'Filters' menu > "Update all subscriptions"

reference: https://support.mozilla.com/questions/896267

Modified by David McRitchie

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Clear the cache and the cookies from sites that cause problems.

"Clear the Cache":

  • Tools > Options > Advanced > Network > Offline Storage (Cache): "Clear Now"

"Remove Cookies" from sites causing problems:

  • Tools > Options > Privacy > Cookies: "Show Cookies"

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).