Bivariate legend plugin throws NameError exception

While using QGIS 3.10 and 3.16 on Mac OS X Big Sur, the Bivariate legend plugin throws a NameError exception. How do I fix this or work around it?

The following stack trace is from QGIS 3.10. The 3.16 stack trace seems similar.

An error has occurred while executing Python code:

NameError: name 'Qgis' is not defined 
Traceback (most recent call last):
  File "/Users/judithheher/Library/Application Support/QGIS/QGIS3/profiles/default/python/plugins/BivariateLegend/bivariate_legend.py", line 400, in generate_image
    level=Qgis.Info
NameError: name 'Qgis' is not defined

Versions:
Python version: 3.7.3 (default, Mar 27 2019, 09:23:15) [Clang 10.0.1 (clang-1001.0.46.3)]
QGIS version: 3.10.11-A Coruña A Coruña, d2171173e4

Python Path:

/Applications/QGIS3.10.app/Contents/MacOS/../Resources/python
/Users/judithheher/Library/Application Support/QGIS/QGIS3/profiles/default/python
/Users/judithheher/Library/Application Support/QGIS/QGIS3/profiles/default/python/plugins
/Applications/QGIS3.10.app/Contents/MacOS/../Resources/python/plugins
/Applications/QGIS3.10.app/Contents/Resources/python
/Applications/QGIS3.10.app/Contents/Frameworks/Python.framework/Versions/Current/lib/python3.7/site-packages
/Applications/QGIS3.10.app/Contents/Frameworks/Python.framework/Versions/Current/lib/python3.7
/Applications/QGIS3.10.app/Contents/Frameworks/Python.framework/Versions/Current/lib/python37.zip
/Applications/QGIS3.10.app/Contents/Frameworks/Python.framework/Versions/Current/lib/python3.7/lib-dynload
/Applications/QGIS3.10.app/Contents/Frameworks/Python.framework/Versions/Current/lib/python3.7/site-packages/geos
/Users/judithheher/Library/Application Support/QGIS/QGIS3/profiles/default/python
/Users/judithheher/Documents/Home/SJSU/GEOG171/Week4