Have Hubspot count the characters included in each email subject line.
In order to meet the best practice of 50 characters or less in email subject lines, it would be ideal if HS counted the characters for you automatically. (Think the "twitter countdown" when composing tweets.)
I completely agree! If Twitter can do it, HubSpot can do it! This would save time, energy and the cumbersome shifting back and forth to a character counter.