[Debugger] Onboarding for Map Scopes

[digitarald]

Background

Map scopes transforms build/compressed into how the original source behaves. It's magical when enabled buy we can't enable it by default as it has performance overhead (especially on the first pause).

It makes several variable-related features more reliable:

• Scopes pane
• Variable hover preview (without it preview will not work at all for original variables)
• Inline variable preview (same breakage as above)
• With 78: Now also mapping in Logpoints (making logging work for original variables)

Problem

The checkbox is so subtle that it's easy to ignore, so users lose out on a better debugging experience.

Solution

Lightweight onboarding to opt users into enabling Map scopes when it's available for a file.

This could be a subtle bar in the Scopes pane on pausing or on top of the file as a lot of variable inspection happens in context of the code.

[digitarald]

cc @janodvarko @loganfsmyth @jaril @jasonLaster

[violasong]

(Unused) example of onboarding styling we could use

[janodvarko]

@violasong, thanks for the mockup, I like that

If I understand correctly, we'd display similar notification message explaining what "Map Scopes" does and perhaps link to MDN - directly within the "Scopes" panel at the top?

I am also attaching a screenshot of what we do for the multi-line Console editor

Honza

[olfek]

The checkbox is so subtle that it's easy to ignore, so users lose out on a better debugging experience.

I just ran into this over at terser/terser#1367