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Modal dialog 0:37
A 37-second explainer of Modal dialog, narrated over the same demo you can try yourself.
Try the interactive Modal dialog demo
What this video covers
A modal dialog overlays the page and requires a decision before you can proceed - everything behind it is disabled. Used well, it focuses attention; used poorly, it traps the keyboard and loses users entirely.
In the broken dialog, Tab leaked out to the page behind and Escape did nothing - so a keyboard user could lose the dialog, or get stranded in it. The accessible one kept focus inside, closed on Escape, and handed focus back to the button you came from. Same window; completely different experience depending on who is at the keyboard.
