Deprecation: #68098 - Deprecate GeneralUtility methods

See forge#68098

Description

The following methods within GeneralUtility have been marked as deprecated and will be removed in TYPO3 CMS v8.

GeneralUtility::modifyHTMLColor()
GeneralUtility::modifyHTMLColorAll()
GeneralUtility::isBrokenEmailEnvironment()
GeneralUtility::normalizeMailAddress()
GeneralUtility::formatForTextarea()
GeneralUtility::getThisUrl()
GeneralUtility::cleanOutputBuffers()

The functionality formatForTextarea() was used in the older days to actually support IE4 and Netscape 3 properly and can now safely be exchanged by htmlspecialchars().

Impact

All extensions using these methods directly will throw a deprecation message.

Affected Installations

Installations with extensions that use the methods above handling.

Migration

Use corresponding functionality from getIndpEnv() instead of getThisUrl().

For the other methods, you can re-implement the functionality yourself in your extension where needed.