- Copy checks the document's copying permission first, then reads the
pages whose text wasn't read for display on a worker thread
(DocumentCopy; in place on the web), keeping only each page's text as
it goes; the clipboard gets the text on a later frame. A new copy or
the document closing cancels it.
- Any press on a page ends Select All of the document, whatever the tool
and whether its text is read; so do switching to one page at a time, a
page selection, and an edit of the document.