Everybody recognizes this situation: you're looking for an extension with a certain functionality and after you've installed it all kinds of errors appear about missing functions or even worse, you only see a blank page. Further investigation shows that the extension isn't compatible with your TYPO3 version.For a long time extensions can set the TYPO3 version(s) they are compatible with. Unfortunately not many extension authors use that setting. You could take a look at the date of publication, but even that won't be a sure sign.
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