okay (#66653)
okay (#66653)

I'm not sure who tested #65379 (a58c8b7fa45154ac4e760ae38961146001fa2e5d) or if this was only a downstream issue,
But it is not true that TGUI inputs can't return null. It returns null if you cancel or hit X.
By changing the isnull check to only look for a falsy value, you can no longer enter a blank text to succumb without last words.
Meaning you MUST enter something to succumb.
This is unintended.

Fixes a bug again. Please allow blank text last words, some people would rather the silent treatment.

I believe this was the result of merge skew, the two prs that proported to fix this issue went through at close to the same time, was likely just a mixup -Lemon 
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