Missing Padding for the bottom modalsheets!

Checklist

• I have used the search function to see if someone else has already submitted the same bug report.
• I will describe the problem with as much detail as possible.

App

Thunderbird for Android

App version

19.0

Where did you get the app from?

Google Play

Android version

Android 15

Device model

Nubia z60s pro

Steps to reproduce

Go to any sent mail

Tap on the information part, bellow the title (the one containing the email address, reply, etc.. )
this brings up a bottom modalsheet dialog.

I have the 3 button navigation enabled on the system, so the very bottom parts of this, and every other bottomsheet dialogs are overlapping with the system ui.
As seen (marked red) on the attached image.

Expected behavior

There should be proper amount of padding applied to all dialogs, so the system ui never blocks content.

Actual behavior

The system UI currently blocks content.

Logs

Start by reproducing the issue from a sent mail: open the information area below the title on Android 15 with three-button navigation enabled, then inspect the bottom modal sheet and other bottom-sheet dialogs. Done means the system UI no longer overlaps any dialog content and the fix applies consistently across the affected sheets.