pg_activity fails with TypeError on start

Hi,

OS: Devuan beowulf (equivalent to Debian buster)

Package: pg-activity=2.1.0-1.pgdg100+1

I have the latest version of pg-activity installed from the buster-pgdg
repository and it fails on startup with a TypeError.

$ pg_activity
Traceback (most recent call last):
File "/usr/bin/pg_activity", line 321, in <module>
ui.main(term, dataobj, host, options, dsn)
File "/usr/lib/python3/dist-packages/pgactivity/ui.py", line 227, in
main
width=width,
File "/usr/lib/python3/dist-packages/pgactivity/views.py", line 526,
in screen
width=width,
File "/usr/lib/python3/dist-packages/pgactivity/views.py", line 123,
in wrapper
for line in func(term, *args, **kwargs):
File "/usr/lib/python3/dist-packages/pgactivity/views.py", line 378,
in processes_rows
cell(getattr(process, field), column)
File "/usr/lib/python3/dist-packages/pgactivity/views.py", line 363,
in cell
text_append(f"{color}{column.render(value)}")
File "/usr/lib/python3/dist-packages/pgactivity/types.py", line 359,
in render
return self.template_h % self.transform(value)[: self.max_width]
File "/usr/lib/python3/dist-packages/pgactivity/utils.py", line 79,
in ellipsis
lv = len(v)
TypeError: object of type 'NoneType' has no len()

I can see in the package information that the upstream source is listed
as https://github.com/julmon/pg_activity. That repository mentions
that it is a fork of the original upstream at
https://github.com/dalibo/pg_activity.

I have tested the latest version of pg_activity 2.1.5 from
https://github.com/dalibo/pg_activity installed via pip in a python3.7
virtual environment and it starts properly without any error.

Can the pg-activity package please be updated to the latest version
2.1.5 from https://github.com/dalibo/pg_activity?

Thanks,
Tom