Hi Alexander,
I moved to new version 26.5 and here my results:
Please see:
Test data(input/output/QGIS)
5369-Gml GeoJsonSeq.zip (54.9 KB)
Thanks,...5369: Gml to GeoJsonSeq- Conversion succeeded, output in QGIS...(gml3.gml) is incorrect for conversion. No root element declaration...