[Bug 48469] New: Pale Moon crashes when loading web page from address bar

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=48469

Bug ID: 48469
           Summary: Pale Moon crashes when loading web page from address
                    bar
           Product: Wine
           Version: 5.0-rc5
          Hardware: x86
               URL: http://www.palemoon.org/download.php?mirror=eu&bits=32
                    &type=7z
                OS: Linux
            Status: NEW
          Keywords: regression
          Severity: normal
          Priority: P2
         Component: msctf
          Assignee: [e-mail]
          Reporter: [e-mail]
   Regression SHA1: d541087079a8770bb02bae830c56a6d3c0b6424e
      Distribution: ---

Since d541087079a8770bb02bae830c56a6d3c0b6424e, Pale Moon (and other
applications reliant on this feature) crashes when e.g. loading web pages
(through address bar especially).

That commit by itself is not wrong. But prior to it, the browser received an
error from the function and disabled all msctf functionality. With that commit,
the bug is now exposed.

What happens is that AssociateFocus does not grab ownership of the Document
Manager, but it does return it in the "prev" output parameter with an increased
refcount. So, if the docmgr gets destroyed and AssociateFocus is called again,
its "prev" parameter will refer to freed memory (dangling pointer). Windows
sets it to NULL in such case.

Sent a patch to fix this.