+1

I think this would be very helpful as the only places I can find its deprecation are a small note at the top of the Tix Python docs [https://github.com/python/cpython/commit/bd63353] and a news entry a long way down the 3.6 release notes https://docs.python.org/3/whatsnew/3.6.html#id7 [https://github.com/python/cpython/commit/ba41c81].

While I agree with @Zachary's comment on #29125 that the injection bug probably would be a reasonable excuse to remove Tix, I believe we should first "properly" deprecate it (I can imagine a few users getting caught out if we remove it without raising a DeprecationWarning in previous versions).

IMO, #31371 should be reopened once this has been merged to facilitate removal in a future version and allow discussion for which version removal should occur in. I also think that we should back-port this to 3.8/9 to give users more notice than they might otherwise get.

@wyz23x2, are you alright to write a patch for this? (I assume no-one has any objections given that Tix is already deprecated)