I have opened this thread so that people can come up with commonly faced bugs and the fixes for the same.
To start with the following bug:
An exploitable vulnerability has been detected in Python mwlib which can be used by people to cause DoS. It is caused by by an error within the regular expression parser when handling #iferror.
The solution to this is: Update to version 0.13.5
I request everyone to follow the same posting pattern for people to understand it better.