Parsing failed for browser and os versions reported to stdout

[Artur-]

Description of the bug

From logs of Start:

Browser engine version parsing failed for: mozilla 5.0 (windows nt 10.0; win64; x64) applewebkit 537.36 (khtml, like gecko) chrome 78.0.3904.97 safari 537.36 opr 65.0.3467.48 For input string: "a 5.0"
Browser major version parsing failed for: 17 sa For input string: "17 sa"
Browser major version parsing failed for: w For input string: "w"
Browser minor version parsing failed for:  For input string: ""
OS major version parsing failed for: /5 For input string: "/5"
OS minor version parsing failed for: 0 (android For input string: "0 (android"
OS minor version parsing failed for: 0) applewebkit/537 For input string: "0) applewebkit/537"

There seems to be two issues here:

1. Parsing fails
2. The error is reported to stdout or stderr instead of through a logger so it took some detective work to even figure out where they come from

Also as the full string that is being parsed is not logged in all cases, it makes things a bit difficult to fix

Expected behavior

No errors are logged without a logger and parsing succeeds

Minimal reproducible example

Versions

• Vaadin / Flow version: 24.6 beta

[tepi]

As for issue 2, in this change this Artur guy explains why stderr is used instead of logging: 791b91c#diff-7354528a0f72607f3d6e1464b30a1fec4ca251c4cda835f7693bdd7cd5159e2bR568-R573

[Artur-]

Always that guy. He is often wrong. Pretty good if nobody noticed or cared for 8 years though

[caalador]

I guess the stderr is because it is also used from the client and Logger is not available there.

What is the logging choice we should use for the shared package that would work both for the server and client?

[Artur-]

There probably is no such thing and it should be logged in different ways on different sides

[mshabarov]

We've merged the patch, let's keep it opened until we release a new version and use it for a while with Start to see if we have a proper logging now and any remaining errors.