Thunderbirds calendar will display the calendar contents.

Or you could download an Sqlite viewer from the internet and read the underlying storage tables, but they will not be formatted in an inteligible way to "just read" they will be database tables of data and indexes.

Thanks for responding, Matt. I'm sorry my query wasn't clear.

I noticed the sqlite databases; I should have mentioned that. Is documentation available for how to interpret their records as calendar entries?

Thanks again for your interest.

Documentation of source data is basically non existent for the entire project. I am not aware of anything useful.

There is a docs folder in the source code repository. But it contains nothing looking like documentation. https://searchfox.org/comm-central/source/docs

I see what you mean. Thanks very much for your help anyway, Matt!