Multi-target to reduce dependencies

[mus65]

Currently, Microsoft.Playwright has a few dependencies which are all unnecessary on modern .NET because they are part of the framework itself. This will become even more of an issue with .NET 9 since NuGet Audit will start complaining about CVEs in transitive dependencies, so all consuming modern. NET applications will get false positive warnings about e.g. a CVE in System.Text.Json .

Multi-targeting would allow to remove these dependencies on modern .NET . It would also allow to conditionally make use of newer APIs in modern .NET.

I could make a PR for this and already looked into this. Unfortunately this is not as simple as editing the csproj since quite a few new warnings are introduced in the net8.0 target which would need fixing or suppressing. So I first wanted to get some feedback on whether a PR for this would be accepted.

[mxschmitt]

Which CVEs are you referring to? We aim to fix security vulnerabilities so we did it with #3016.

[mus65]

I'm referring to CVEs in general. Currently a CVE in System.Text.Json would affect both .NET Framework and modern .NET applications. With multi-targeting, only .NET Framework applications would be affected since the dependency isn't even needed on modern .NET. So something like #3016 would not be necessary in the first place (at least for modern .NET users).

[mxschmitt]

Lets collect feedback for it. So far we didn't see much demand for it. Multi-targeting means having compiler directives inside the code which adds a lot of overhead for us to maintain the library, also testing wise these are then different code-paths etc.

[kblok]

My two cents. Some libraries have different implementations, whether you use the netstandard version or the .NET 8 version, for good or bad.
The good part is that you might get a bump in performance if you use .NET-specific libraries and fewer dependencies. The bad part is that you might have different behaviors (potential bugs) on different platforms.