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Firefox doesn't display some text on certain pages.

  • 4 replies
  • 4 have this problem
  • 3 views
  • Last reply by crazypays

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I've noticed that on some pages, Firefox doesn't display certain text. I have the newest version of Firefox installed and my flash and java are updated. The text displays fine on Chrome and IE. Please see my example in the screenshots of the stevenson.edu webpage. Does anybody know what I can do to fix this problem or if there is some sort of plugin I am missing to display certain content? Thanks.

Screenshot of Firefox: http://i47.tinypic.com/123359k.jpg Screenshot of Chrome: http://i48.tinypic.com/2uy3ay1.jpg

I've noticed that on some pages, Firefox doesn't display certain text. I have the newest version of Firefox installed and my flash and java are updated. The text displays fine on Chrome and IE. Please see my example in the screenshots of the stevenson.edu webpage. Does anybody know what I can do to fix this problem or if there is some sort of plugin I am missing to display certain content? Thanks. Screenshot of Firefox: http://i47.tinypic.com/123359k.jpg Screenshot of Chrome: http://i48.tinypic.com/2uy3ay1.jpg

Chosen solution

The site appears to be using an older 1.2.0 version of MooTools that is not compatible with curent Firefox releases.

Quote: Mootools 1.2.x incompatible with Firefox 18 and newer.Fixed in Mootools 1.3 and newer (see 789036)


  • bug 789036 - MooTools 1.2.x was broken by adding String.prototype.contains

(please do not comment in bug reports: https://bugzilla.mozilla.org/page.cgi?id=etiquette.html)

Read this answer in context 👍 1

All Replies (4)

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Many site issues can be caused by corrupt cookies or cache. In order to try to fix these problems, the first step is to clear both cookies and the cache. Note: This will temporarily log you out of all sites you're logged in to. To clear cache and cookies do the following:


  1. Go to Firefox > History > Clear recent history or (if no Firefox button is shown) go to Tools > Clear recent history.
  2. Under "Time range to clear", select "Everything".
  3. Now, click the arrow next to Details to toggle the Details list active.
  4. From the details list, check Cache and Cookies and uncheck everything else.
  5. Now click the Clear now button.

Further information can be found in the Clear your cache, history and other personal information in Firefox article.

Did this fix your problems? Please report back to us!

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Thank you for the response. I have tried deleting the cache and cookies and I still have the same problem. Are you able to view that website correctly on Firefox?

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Chosen Solution

The site appears to be using an older 1.2.0 version of MooTools that is not compatible with curent Firefox releases.

Quote: Mootools 1.2.x incompatible with Firefox 18 and newer.Fixed in Mootools 1.3 and newer (see 789036)


  • bug 789036 - MooTools 1.2.x was broken by adding String.prototype.contains

(please do not comment in bug reports: https://bugzilla.mozilla.org/page.cgi?id=etiquette.html)

Modified by cor-el

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Great, thanks. I just wanted to make sure that nothing was wrong with my installation of Firefox or with my computer. I appreciate the help.