1. Make sure you're using GtkSalMenu. 2. Customize main menu, e.g. in File move "Open..." above "New". 3. The menu still looks like before, but clicking "Open..." will execute the "New" command.
This is proving tricky. It might be easier if the actiongroup and menumodel were available right at the start of this ball of mud. So I'll see if https://gerrit.libreoffice.org/23287 will build on all platforms and that might allow an easier approach.
Caolán McNamara committed a patch related to this issue. It has been pushed to "master": http://cgit.freedesktop.org/libreoffice/core/commit/?id=86f504ee014d17172267f14742b8edd5789cbbc6 Related: tdf#98637 make this a tractable problem It will be available in 5.2.0. The patch should be included in the daily builds available at http://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More information about daily builds can be found at: http://wiki.documentfoundation.org/Testing_Daily_Builds Affected users are encouraged to test the fix and report feedback.
https://cgit.freedesktop.org/libreoffice/core/commit/?id=d20e08a3ab819ac24f7ea49a98b4dd3683120857 seems to fix this the way I wanted