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[ickby]

Thank you for creating a pull request to contribute to FreeCAD! To ease integration, please confirm the following:

• Branch rebased on latest master git pull --rebase upstream master
• Unit tests confirmed to pass by running ./bin/FreeCAD --run-test 0
• Commit message is well-written
• Commit message includes issue #<id> or fixes #<id> where <id> is the associated MantisBT issue id if one exists

And please remember to update the Wiki with the features added or changed once this PR once it is merged.

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This pull request further details and implements the GeoFeatureGroup datastructure in FreeCAD:

• PR introduces "scopes" to links to decide where they are allowed to go to in respect to GeoFeatureGroup
• "out of scope" links are now reportet as error during recompute
• Special scoped link properties are created
• Multiple bugs with groups and geofeaturegroups are fixed
• Backlink structure is fixed and reenabled to improve performance of many group operations

[sasobadovinac]

does this only need to be reviewed or is there also something else preventing it from getting merged?

[peterlama]

Have a look at the forum thread: https://www.forum.freecadweb.org/viewtopic.php?f=10&t=20749&start=30#p187270

[wwmayer]

Merged.