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Since upgrading to 4.0, when I type in a text box vertical lines appear underneath each character as I am typing. How can I get this to stop?

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  • Last reply by cor-el

comagirl
comagirl
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Since upgrading to 4.0, while typing in any text box vertical lines appear underneath each character as I am typing. How can I stop this from happening?

Since upgrading to 4.0, while typing in any text box vertical lines appear underneath each character as I am typing. How can I stop this from happening?

All Replies (2)

Xircal
Xircal
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What colour are they?

cor-el
cor-el
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  • Top 10 Contributor
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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the add-ons is causing the problem (switch to the DEFAULT theme: Tools > Add-ons > Appearance/Themes).

  • Don't make any changes on the Safe mode start window.

In Firefox 4 Safe mode disables extensions and disables hardware acceleration.
Check if there is an update available for your graphics display card driver.

  • Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available"