TYPO3 Core

The problem happens when user enters external URL in the RTE. Suppose you have two domains: domainA and domainB. You are currently logged in to http://domainA/typo3/ and edit a page that belong to domainB. Now you want to add external URL to the text. This external URL looks like http://domainA/page/. You expect that domainB will show it as http://domainA/page/ but TYPO3 transforms it to become http://domainB/page/ (actually it just strips host part from the external URL).

Technical info: =============
The problem is in the t3lib_parsehtml_proc::urlInfoForLinkTags function. It determines URL type incorrectly.

This function does not detect correct URL type when user enters external URL and that URL contains the same host part as the current BE host. The function treats such case if link is a link to a file and modifies external URL. This causes wrong external URL. There is no way to force TYPO3 produce correct external URL in such case.

(issue imported from #M9679)