Plugin causes Fatal error in backend

[robert-heinig]

TYPO3 7.6.9 t3users 2.0.3

When trying to access a page where the FE-plugin was created: Fatal error: Cannot create references to/from string offsets nor overloaded objects in [path]/typo3/sysext/extbase/Classes/Service/FlexFormService.php on line 50 Selected view does not seem to matter.

The key "feuseredit.doubleoptin.pid" seems to be the problem. My guess is, that there shouldn't be flexform keys used which are prefixes of ther keys (in this case "feuseredit.doubleoptin" is also a key).

There also is a core bug: https://forge.typo3.org/issues/46049

[hannesbochmann]

I can't reproduce this behaviour. Can you please check several things.

• Which PHP version do you use?
• Do you have the flux extension installed?
• Can you attach a stack trace of the fatal error?
• Does the error occur when you enter the page module in the backend or when is it triggered?
• Maybe the tt_content element was used for another plugin before using t3users. This can leave some leftover old configuration in the element. If that's the case, please delete the tt_content element and recreate it with the t3users plugin.
• Maybe another extension is causing this trouble. Can you deactivate all other 3rd party extensions one by another checking after each one if the error persists? Or you tell me which extensions you have installed.