F5 on a virtual document pop FileDialog

[zhfnjust]

Version: 1.54.1 (user setup)
Commit: f30a9b7
Date: 2021-03-04T22:38:31.419Z
Electron: 11.3.0
Chrome: 87.0.4280.141
Node.js: 12.18.3
V8: 8.7.220.31-electron.0
OS: Windows_NT x64 10.0.18363

Steps to Reproduce:

1. open a virtual document, such as the office virtual-document-sample

2. press F5, it pop a FileDialog that is not expected, i just want to debug my code, not save file. I think it's a bug.

Does this issue occur when all extensions are disabled?: Yes

[isidorn]

Use this setting

"debug.saveBeforeStart": "nonUntitledEditorsInActiveGroup",