TYPO3 Core

Check for supported browser is in typo3/sysext/rtehtmlarea/htmlarea/htmlarea.js. Check for isIE comes from ExtJS.

Would it be possible for you to check if an upgrade of ExtJS might help you? Patch against current master is at: https://review.typo3.org/24883
But the release-notes also only point to "support for IE10". But let's see ...

Can you maybe use a JS-debugger and see inside htmlarea.js what value the variables like isIE etc. have?

Thank you for your help. I will take a look at it and report back here.

This phenomenon also occurs in Typo3 4.7 and 6.2

Could this have anything to do with the changed useragent string of IE 11 ?

See: http://en.wikipedia.org/wiki/Internet_Explorer_11

It is now in the format of:
Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko

rv:11.0 instead of MSIE

The same as #54122

Actually, that one was dupe.

See:
http://forge.typo3.org/issues/54124
http://forge.typo3.org/issues/53818

This can be closed for as far as I can see.

This is not really a dupe of #54122 or #53818.

This is related to the changed useragent string of IE 11 and ExtJS browser sniffing!

In the backend, there is a <meta http-equiv="X-UA-Compatible" content="IE=10" /> (typo3 6.2) or <meta http-equiv="X-UA-Compatible" content="IE=9" /> (typo3 4.7) , so the IE11 useragent string does not contain "like gecko" and is sniffed as "isGecko=false".
So the RTE works in the Typo3 backend.

But if you want to use the RTE in the frontend, and also want to stay in "IE=edge", the htmlarea fails to initialize because it is sniffed as "isGecko=true".

A short fix , in (typo3 4.7 and 6.2) file: typo3/sysext/rtehtmlarea/htmlarea/htmlarea.js:

--- src: Ext.isGecko ? 'javascript:void(0);' : (Ext.isWebKit ? 'javascript: \'' + HTMLArea.htmlEncode(this.config.documentType + this.config.blankDocument) + '\'' : HTMLArea.editorUrl + 'popups/blank.html')
+++ // IE11 sometime pretends to be "like gecko". That's ok for Ext DOM related work, but not for the security model
+++ src: (Ext.isGecko && typeof document.baseURI !== 'undefined') ? 'javascript:void(0);' : (Ext.isWebKit ? 'javascript: \'' + HTMLArea.htmlEncode(this.config.documentType + this.config.blankDocument) + '\'' : HTMLArea.editorUrl + 'popups/blank.html')

I think that in the long term, rtehtmlarea should avoid using ExtJS "useragent string based" browser sniffing.

I agree with Guillaume. When using the RTE in the Frontend, one cannot just set IE=10 for a website. Guillaume's solution is very straight-forward until ExtJS is updated. document.baseURI doesn't exist in IE, therefore this solves the problem in the meantime.