Hi Halvor,
The extensions location in the Connect Web application as shown in your screenshot is not correct. It has to be added in a different location.
Please add the URL
:https://trimble-connect-marker-authoring.trimble.com/ in the Connect's 3D Viewer "CUSTOM EXTENSIONS" page as shown in screenshot below.
1. Please access
https://3d.connect.trimble.com 2. From the left panel click on Settings > Custom extensions
3. Add the above mentiond URL In the field Plugin Application URL

The Marker extension should appeal in the left panel after these steps. In case you continue to face issues, please get in touch with
ftgsupport@trimble.com.
cc// @Ben Broad
Regards
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Darshan Rajaram Kamat
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