NVDA (and possibly other AT products) primarily walks the tree using IAccessibleText and retrieves embedded objects using IAccessibleHypertext, rather than using AccessibleChildren. Unfortunately, as noted in bug 1363595 comment 21, accessibles retrieved by using IAccessibleHypertext::hyperlink do not use the handler, so caching isn't used. This effectively means that for clients that use this technique, the cache is only used for the top level document or, in the case of handling updates, the root of the subtree being updated. This occurs because IAccessibleHypertext::hyperlink returns an IAccessibleHyperlink. The handler provider and handler do not know about this interface, and thus the handler isn't used. The client then does a QI to IAccessible2, but because they're doing this on a standard proxy, they still don't get the handler. We need to teach the handler provider and handler about IAccessibleHyperlink. Note that the handler is already used correctly for accessibles retrieved via AccessibleChildren. From what I can see, JAWS does not use IAccessibleHypertext, so this probably won't have any benefit for JAWS.

Comment on attachment 8919980 [details] Bug 1409928: Use e10s a11y handler cache for accessibles retrieved via IAccessibleHypertext. https://reviewboard.mozilla.org/r/190924/#review198742

We need to hold off on landing this until the dependent bug merges to central, so I'm going to clear this for now and then I'll land it once that happens.

We're sorry, Autoland could not rebase your commits for you automatically. Please manually rebase your commits and try again. hg error in cmd: hg rebase -s 22626b0eb821 -d 681b41afb3ee: rebasing 430439:22626b0eb821 "Bug 1409928: Use e10s a11y handler cache for accessibles retrieved via IAccessibleHypertext. r=aklotz" (tip) merging accessible/ipc/win/HandlerProvider.cpp merging accessible/ipc/win/handler/AccessibleHandler.cpp warning: conflicts while merging accessible/ipc/win/HandlerProvider.cpp! (edit, then use 'hg resolve --mark') unresolved conflicts (see hg resolve, then hg rebase --continue)

We're sorry, Autoland could not rebase your commits for you automatically. Please manually rebase your commits and try again. hg error in cmd: hg rebase -s 22626b0eb821 -d 681b41afb3ee: rebasing 430439:22626b0eb821 "Bug 1409928: Use e10s a11y handler cache for accessibles retrieved via IAccessibleHypertext. r=aklotz" (tip) merging accessible/ipc/win/HandlerProvider.cpp merging accessible/ipc/win/handler/AccessibleHandler.cpp warning: conflicts while merging accessible/ipc/win/HandlerProvider.cpp! (edit, then use 'hg resolve --mark') unresolved conflicts (see hg resolve, then hg rebase --continue)

Rebased on top of the submission changes to the dependent patch.

Pushed by aklotz@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/4fdd6f569847 Use e10s a11y handler cache for accessibles retrieved via IAccessibleHypertext. r=aklotz