[Portal 2] After epilogue FMV plays, the game crashes

[Dogman15]

It seems that a number of people, both reporting on Steam and as seen in Let's Plays on YouTube, are encountering a bug where after "sp_ending_callback.bik" plays (the cutscene of Wheatley and the Space Core orbiting him), the game either crashes, or it stays on a black screen instead of going back to the main menu (menu_act05.bik while the music "Space Phase" plays).

Some people have reported that the issue was fixed for them by:

1. playing on borderless fullscreen windowed, or just windowed
2. pausing the game during the final cutscene (which does not pause video playback) and bringing up the Steam overlay
3. disabling "wait for vertical sync"
4. not putting shader detail on "very high" Or any combination of these, possibly all or just one. As outlined in some of the responses to this discussion topic on the Steam forums: https://steamcommunity.com/app/620/discussions/0/3044978964799136435/

One person has made a guide to help others: https://steamcommunity.com/sharedfiles/filedetails/?id=3014856840

However, I have tried all of these things, and the game would still crash for me after the Wheatley/Space Core cutscene. This happened both when I would load up "map sp_a5_credits" and wait, and also if I started a "new game" from the main menu.

Here is one video I could find where I have seen this happen: https://www.youtube.com/watch?v=trrIJuZt3Kg (1:05:08) Another (1:30:15 - after sp_ending_callback, the player does not show the menu at all, implying it didn't appear): https://www.youtube.com/watch?v=nVsj0QOIt28