How to enable quick look preview in OmniOutliner 3.10.6 on osx11.2?

Question

After installing El Capitan, the contents of OmniOutliner Pro 3.10.6 files are no longer visible (I know there is a newer version but I'm not interested spending the money).

Is there a way to re-enable quick look?

Answer 1

Download a recent version of OmniOutliner, in my case I used 'OmniOutliner-4.4.1.dmg'

Mount the dmg and right click on the app icon and choose 'Show Package Contents'

Navigate to:

'OmniOutliner.app/Contents/Library/Spotlight/OmniOutlinerMetadataImporter.mdimporter'

and copy it to:

'/Library/Spotlight/OmniOutlinerMetadataImporter.mdimporter'

Also find this file:

'OmniOutliner.app/Contents/Library/QuickLook/OmniOutliner.qlgenerator'

and copy it to:

'/Library/QuickLook/OmniOutliner.qlgenerator'

Quick Look will now work again.