Widget index / Windows and dialogs · Download this HTML
Ready — try the example.
States and behavior
Cross-page draft, Apply enabled only when changed, OK commit/close, Cancel rollback since last Apply, explicit caption Close decision.
Keyboard
Arrows switch tabs; Tab enters fields; Escape inside the sheet acts as Cancel. Caption Close offers Apply, Discard, or Keep editing when dirty.
Scope and adaptation
A fixed-object modeless property sheet. Apply commits every page and Cancel never undoes an earlier Apply. The draft’s distinct Close behavior is modeled explicitly here; it is not a requirement to prompt on every dialog’s X.
Sources
Microsoft preliminary guide (1995), chapters 7–8 · Modern browser accessibility pattern
Original implementation; system colors are represented by CSS variables. The default 13 px system-font stack is a readable browser adaptation. The 1995 source is preliminary, not a final product specification. Test the target browser and native host before shipping.