Steps to reproduce:

1. I was in a Gmail conversation.
2. Pressed Space on the More Actions for the conversation in the upper tool bar.
3. Arrowed down in the menu, wanted to add a filter. Got to the Add To Tasks item.
4. Press DownArrow once more.

Actual behavior:

Reproducible crash that closed Firefox. Sometimes, Crash Reporter doesn't even come up. But once it did, and it gave me this crash report.

Expected behavior:

No crash.

System configuration:

NVDA Installed/portable/running from source:

Installed.

NVDA version:

NVDA version alpha-16220,87eb36f8

Windows version:

Windows 10 insider 18272.

Name and version of other software in use when reproducing the issue:

Firefox 65.0a1 Nightly from November 6.

Other information about your system:

Gmail is in New Design, I believe this is the default now, and you cannot eve turn that off any more. It's the standard Gmail, not G Suite.

Other questions:

Does the issue still occur after restarting your PC?

Yes. Reproducible on my system.

Have you tried any other versions of NVDA?

Yes, 2018.3.x does not crash. I suspect this is a result of either the VBuf speedup or the merging of DLLs, or both.

CC @michaelDCurran @jcsteh.