svn Error messages when using svn co or svn up

[GerdP]

I follow the instructions on https://josm.openstreetmap.de/wiki/Source%20code#Getthesource
with

svn co https://josm.openstreetmap.de/osmsvn/applications/editors/josm

Later I try to update and see

C:\josm>svn up
Updating '.':

Fetching external item into 'plugins\imagery_cachexport\i18n':
External at revision 36216.


Fetching external item into 'core':
External at revision 19004.


Fetching external item into 'plugins\00_core_test_config':
External at revision 19004.


Fetching external item into 'plugins\00_core_test_lib':
External at revision 19004.


Fetching external item into 'plugins\00_core_tools':
External at revision 19004.

svn: warning: W205011: Error handling externals definition for 'plugins\building_generalization':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/Building-Generalization/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\Color':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/Color/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\Dxf-Import':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/Dxf-Import/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\Mapillary':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/Mapillary/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\maproulette':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/MapRoulette/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\PicLayer':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/PicLayer/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\shapetools':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/ShapeTools/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\areaselector':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/areaselector/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\austriaaddresshelper':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/austriaaddresshelper/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\auto-tools':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/auto-tools/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\changeset-viewer':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/changeset-viewer/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\configuration':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/configuration/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\conflation':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/conflation/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\continuosDownload':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/continuos-download/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\improve-way':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/improve-way/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\indoorhelper':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/indoorhelper/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\kartverketimport':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/kartverketimport/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\osm-obj-info':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/osm-obj-info/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\pt_assistant':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/pt_assistant/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\rex':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/rex/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\todo':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/todo/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\turnlanes-tagging':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/turnlanes-tagging/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\validations_testing':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/validations_testing/trunk'
svn: warning: W205011: Error handling externals definition for 'plugins\wikipedia':
svn: warning: W170013: Unable to connect to a repository at URL 'https://github.com/JOSM/wikipedia/trunk'
At revision 36216.
svn: E205011: Failure occurred processing one or more externals definitions

C:\josm>

Is this a problem on the server side or can I change something? I see this on two different systems using different versions of the svn client.
This log was created with version 1.14.1:

d:\josm>svn --version
svn, version 1.14.1 (r1886195)
   compiled Feb  9 2021, 20:19:00 on x86-microsoft-windows

[stoecker]

Closed as duplicate of #23286.