Recently, in a project for a client where we needed to make the application ADA compliant ie. keyboard accessible, we damn nearly pulled our hair out trying to figure out why, in spite of the fact that every button had been assigned an unique tabIndex value, we were still unable to tab to it. Turned out that the “tabChildren” property of the parent clip and its parent and so forth, all had to be set to “true”. I had thought that that was only necessary if one wanted the tabIndex to be automatically assigned to a particular movieclip’s child clips. Contrary to Adobe’s documentation, this turns out not to be the case. Very strange indeed.