Don't waste your time like I did. This is a QGIS bug. I spent several days trying to solve this issue.
There is no solution at the moment.
I posted the same issue on QGIS bug report. I don't know what developers
did, but after version 3.2.3, GeoJSON files doesn't work on windows OS (it creates a temp file on the same location and all the edits only ...
Take the result of the Skeletonize method and remove the short line segments.
Since the output is a single feature, first split the segments into separate features. The tool Multipart to single parts should achieve this. If not, you may need to resort to Explode lines, which will split the line apart at the vertices.
Select the short lines with the Select ...
To import DWG you don`t need to find geopackage, you need to create one to store data from DWG into.
Geopackage is data format similar to shapefile..
To import DWG select name and location of gepackage to be created, coordinate system of your data (CRS) and location of .dwg file. When DWG is loaded select layers to be imported:
If data isnt georeferenced ...