Qt Failed opening project “xxx“: No plugin can open project type “text/plain“

After going out for a while, QT couldn’t open the project when he came back, so Baidu took it
it turns out that the plug-in is not enabled, so just check it
the top menu bar – help – about plug-ins
check QBs, qmake and support for project construction

Restart QT creator and try to build again. It is successful.

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