Before upgrading a TYPO3 project to a major version (e.g., v7 to v9), we must conduct an in-depth technical analysis by checking compatibility and dependencies (with the TYPO3 core) of all installed extensions.
To do so, you must manually prepare a 3rd party TYPO3 extension compatibility report. This is a bit of a time-consuming task; you have to prepare a list of installed extensions and check each compatibility version one-by-one extension at the TYPO3 Extension Repository (TER) etc..
To save time and energy for the project planning and estimation, our team at NITSAN decided to develop a cool tool to generate an automatic extension compatibility report, and the result is wonderful - EXT:ns_ext_compatibility TYPO3 extension. The extension has more than 2000+ downloads from the TER and Packagist.