It looks like this one you fixed somewhat since your post.
It works better unpinned, see my fork here.
Or click to launch here:
When that notebook comes up you can press ‘Appmode’ icon on the toolbar just like before.
You need to specify to open with the classic mode in the URL of your launch badge. MyBinder recently switched to JupyterLab as the default, see here. (I’m not sure why JupyterLab isn’t getting installed without specifying it right now; I think that is a current glitch perhaps as neither the requirements.txt example or the conda example show specifying it. The announcement specifically said Docker installs would need to install JupyterLab. ==> UPDATE: I tracked this down to nbinteract. Addition of that under the pip section in the environment.yml file causes JupyterLab not to be installed as is the typical default. Probably nbinteract would do the same if added in requirements.txt since I saw JupyterLab installation by the MyBinder system not happen when it was there.)
The big thing I did was move the environment.yml file to binder directory and unpin everything. Since most of what you had there could be handled by mamba, I also transferred the bulk of it installation over to mamba/conda.
Actually except for then needing to activate appmode extension separately, you could do the entire install with requirements.txt. I did that without separate appmode activation as a test, see here. You can launch using that commit here. Appmode doesn’t work there as I didn’t do the separate step of activating the extension in a postBuild or start configuration file.