Chrome Version: 60.0.3088.3
Operating System: Mac OS X 10.12.4

URL (if applicable) where crash occurred: http://persistent.info/chromium/test-cases/post-message-crash.html

Can you reproduce this crash? Always

What steps will reproduce this crash? (If it's not reproducible, what were you doing just before the crash?)
1. Ensure that the LastPass extension installed (https://chrome.google.com/webstore/detail/lastpass-free-password-ma/hdokiejnpimakedhajhdlcegeplioahd/related?hl=en-US). You do not need to be signed in.
2. Open http://persistent.info/chromium/test-cases/post-message-crash.html
3. Press the "postMessage with transfer" button. The tab should crash.

****DO NOT CHANGE BELOW THIS LINE****
Crash ID: crash/e27b1c08d0000000