Error after closing tabs in the Chrome browser

Sounds like a timing issue.  The check for "tab closed" may be happening faster than the actual close.  There are various ways to handle this:

• Use one of the various Wait functions in a loop to check on the tab and if it's still there, wait and check again

• Put a hard delay right before checking for the closed tab

• Change your project settings to wait just a little longer between the execution of each line of the test
• ??? other people's favorite ideas