Improving documentation for built-in type declarations

Looking at for instance lib.dom.d.ts, what I notice is that the documentation isn't what it could be. Is there any policy w.r.t. improving on this? I think the benefits of better docs are quite obvious, for instance adding examples or stating browser support for certain features.

However I wonder if:

• Since the file is already quite large, and adding documentation could blow it up like 100x, would this cause any performance issues (in editors)? If so, is there a way around it?
• The best documentation on these things (that I know of) are on MDN. A nice start could be to link/auto add some docs from there, if the licensing allows it (https://wiki.developer.mozilla.org/en-US/docs/MDN/About#Copyrights_and_licenses). I think it does at least in part.

Beginne mit der Durchsicht von lib.dom.d.ts und den Fragen des Issues zur Größe der Dokumentation, zur Editorleistung und zur MDN-Lizenzierung. Vergleiche die bestehenden Deklarationen mit dem referenzierten MDN-Material. Dieses Issue ist erst abgeschlossen, nachdem sich das Projekt auf eine Dokumentationsrichtlinie und einen konkreten, akzeptierten Ansatz geeinigt hat.