Thanks for your report.

When you say "just one tab", which tab do you mean, and what sort of crash do you see? Command-w is supposed to close a tab in Chrome, so the expected behavior is:

1) Create two tabs
2) Navigate the second one to https://www.youtube.com, start a video, fullscreen it
3) Hit cmd-w
4) Video tab vanishes, first tab is showing again

What do you see happen instead at step 4?

Sorry, I didn't mean one tab. I meant that by pressing command-w without exiting the fullscreen will cause all of Google Chrome to crash. If I press escape then press command-w, everything would be fine. It just crashes when you don't exit fullscreen. 

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For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Thanks for following up.

Do you have a crash ID? Check chrome://crashes - you're looking for the server crash ID (not the local crash ID).

This crash seems to only occur when you command-w on a video that is live-streaming, such as WatchESPN or another live-streaming website. I don't know what the server crash ID is, but this is what I see (Uploaded Crash Report ID a34f9053d032d390 (Local Crash ID: d8c0f989-af9f-4de0-9c1c-3599cc2f2f39)).

I've also pasted the crash information below.

Chrome Version: 65.0.3325.181
Operating System: Mac OS X 10.13.3

URL (if applicable) where crash occurred:

Can you reproduce this crash?

What steps will reproduce this crash? (If it's not reproducible, what were you doing just before the crash?)
1.
2.
3.

****DO NOT CHANGE BELOW THIS LINE****
Crash ID: crash/a34f9053d032d390

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For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Got it, thanks - "a34f9053d032d390" was the crash ID we needed. That ID reveals that this is a known bug: issue 673728. I'm marking this issue as a duplicate of that one.