CK MacLeod on "[Plugin: WP to Twitter] Tweets no longer consistently truncated - 403/186 Errors"

In recent weeks or months, I have frequently had WP to Twitter auto-tweets refused along with the following explanation:

403 Forbidden: The request is understood, but has been refused by Twitter. (Error Code: 186: Status is over 140 characters.)

I have not changed any of the code which used to work fine - always automatically truncating tweets to 140 characters. Now they frequently fail as above.

It's an annoyance that somewhat defeats the main utility of the plug-in, though the tweets at least can still be edited via the metabox, and eventually sent. Some Tweets that appear as though they ought to fail - e.g., because their tags if not partially removed would exceed charaacter limits - don't.

https://wordpress.org/plugins/wp-to-twitter/