All reports of vcs-field-has-unexpected-spaces for the archive. The extended description of this tag is:
The VCS-* field contains more spaces than expected or spaces at places where they were not expected. Where possible, escape valid spaces in URIs to avoid any ambiguity with respect to possible future additional optional fields.
This may be caused by incorrect use of the -b branch separator.
Refer to Debian Policy Manual section 5.6.26 (Version Control System (VCS) fields) for details.
This tag has not been emitted in any package tested by Lintian.