[Regression] Version 7.1.0/7.1.2 inhibits Alt+NUMBER keyboard shortcuts - despite not actually using them!

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## Description

When I have jupyter (either a notebook, or even just the "Home" screen) open, the browser shortcuts Alt+NUMBER (e.g. Alt+1 to switch to the first open tab in the current window) are inhibited. This is very annoying for whoever used to rely on them (*in particular* to switch between different jupyter notebooks!), and pretty weird given that jupyter is apparently not using these shortcuts for anything.

This is a regression because the bug is not there with jupyter 6.4.12 (tested with the same OS/browsers).

Note that even within a same window, the shortcuts will work regularly whenever the currently open tab has something else than jupyter in it. I can also use the shortcuts to move *to* a jupyter tab, but not to go back.

The Ctrl+PgUp/Ctrl+PgDown shortcuts are unaffected by the bug.

## Reproduce

1. Launch jupyter in a new browser window
2. Launch a notebook, which will open in a new tab
3. Pres Alt+1 to go back to the "Home" window

... nothing happens.

## Expected behavior

Switching to the first tab, which in the example above would be the jupyter "Home" screen.

## Context

- Operating System and version: Debian Linux 12 (bookworm)
- Browser and version: tested with both Firefox 115.7.0esr, and Chromium 121.0.6167.139
- Jupyter Notebook version: 7.1.0, tested also with 7.1.2