According to django doc on APPEND_SLASH:
"When set to True, if the request URL does not match any of the patterns in the URLconf and it doesn’t end in a slash, an HTTP redirect is issued to the same URL with a slash appended. Note that the redirect may cause any data submitted in a POST request to be lost." (https://docs.djangoproject.com/en/3.0/ref/settings/)
This means if you want an url to work, with or without trailing, you should modify the original url to have a trailing slash. After that when APPEND_SLASH automatically adds a trailing slash to input url that does not end with trailing slash, it will match the original url.
According to django doc on APPEND_SLASH: "When set to True, if the request URL does not match any of the patterns in the URLconf and it doesn’t end in a slash, an HTTP redirect is issued to the same URL with a slash appended. Note that the redirect may cause any data submitted in a POST request to be lost." (https://docs.djangoproject.com/en/3.0/ref/settings/)
This means if you want an url to work, with or without trailing, you should modify the original url to have a trailing slash. After that when APPEND_SLASH automatically adds a trailing slash to input url that does not end with trailing slash, it will match the original url.