[Bug]: webContents.getUserAgent() is empty since 20.0.0-alpha.6

[Kilian]

Preflight Checklist

• I have read the Contributing Guidelines for this project.
• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for a bug report that matches the one I want to file, without success.

Electron Version

20.0.0-alpha.6

What operating system are you using?

Ubuntu

Operating System Version

Ubuntu 20.04

What arch are you using?

x64

Last Known Working Electron version

20.0.0-alpha.5

Expected Behavior

webContents.getUserAgent() returns a string with a user Agent

Actual Behavior

webContents.getUserAgent() returns an empty string

Testcase Gist URL

https://gist.github.com/33fd4a9ac6db6b28b1dcc5b765edb622

Additional Information

In the console the user agent is printed in alpha.5, but empty in alpha.6. Looking at the diff between alpha.5 and alpha.6, this PR seems the likely cause: #34524 / #34481

It's worth noting that the renderer does have a filled-in userAgent.

[TheMightyPenguin]

I'm also getting this same issue in 19.0.9!