Describe the bug

I recently found an issue where I could not link to headers containing digits.
The link targets were automatically generated with autosectionlabels and work fine locally.

Using sphobjinv I can also verify that all link targets are generated in the objects.inv file.
However, I cannot access headers via interspinx that contain more than one number separated by spaces.

I presume that there is an issue with intersphinx' conversion/evaluation of the objects.inv file.

How to Reproduce

I created a small example tthat reproduces the error here:
https://github.com/Thosse/Playground_GH_Pages

The corresponding Github page can be found here:
https://thosse.github.io/Playground_GH_Pages/

Environment Information

This was reproduced on a manjaro arch linux and Windows 10

Sphinx extensions

['sphinx.ext.autosectionlabel']

Additional context

No response