Edited releases/1.4.txt changes from [17354]

The :tfilter:`urlize` filter no longer escapes every URL

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When an URL contains a ``%xx`` sequence, where ``xx`` are two hexadecimal

digits, :tfilter:`urlize` assumes that the URL is already escaped, and doesn't

apply URL escaping again. This is wrong for URLs whose unquoted form contains

a ``%xx`` sequence, but such URLs are very unlikely to happen in the wild,

since they would confuse browsers too.

When a URL contains a ``%xx`` sequence, where ``xx`` are two hexadecimal

digits, :tfilter:`urlize` now assumes that the URL is already escaped and

doesn't apply URL escaping again. This is wrong for URLs whose unquoted form

contains a ``%xx`` sequence, but such URLs are very unlikely to happen in the

wild, because they would confuse browsers too.

``assertTemplateUsed`` and ``assertTemplateNotUsed`` as context manager

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