In Writer you can set an option to align a frame to the "inner" or "outer" side of a mirrored page layout. However if you want to have text flowing around the "other" side of the frame with some separation between, you'll have to add some spacing between the frame and the surrounding text.
It is not possible to set a left or right spacing in a way that it is reflecting the "inner" or "outer" alignment of the frame: Either you have no spacing at all, or you have spacing at both sides (which breaks "inner" or "outer" alignment to the amount of spacing specified).
I agree on the impossibility (LibO 18.104.22.168 rc1 on Win7).
Enhancement, not bug. I let triage people check and manage the Status accordingly.
Can you confirm that this feature is not available in 4.1.6 and 4.2.5? And if so, can you provide some screenshots of its behaviour.
It's not available in 4.1.6 (or I couldn't find it); give me some time for the rest...
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Part 1 for LibreOffice 4.1: Settings
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Part 2 for LibreOffice 4.1: Settings
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Part 1 for LibreOffice 4.2: Settings
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Part 2 for LibreOffice 4.2: Spacing not mirrored for opposite page
Thank you for the confirmation. I've set this issue as an enhancement as Dominique forgot to set it.