Use short-links in Publish

For Facebook, Write out full link, after it appears in preview remove the link. Twitter will automatically shorten the link when published

For Facebook:

Step 1: Type the link in the text field and see it appear in the preview, Press Enter

Step 2: Mark and delete the link from the text field

Step 3: The link is still visible in the preview --> Publish the post

What it will looks like on Facebook.com

 

 

For Twitter

Twitter will automatically shorten the link and take that into account when calculating how many characters are left of the tweet