Application shifts when pressing 'Page Down' in a textarea inside mat-sidenav-content when mat-sidenav[position] is set to "end"

[joerideg]

Reproduction

Use StackBlitz to reproduce your issue: https://stackblitz.com/edit/angular-material-breaking-sidenav

Steps to reproduce:

1. focus on the textarea
2. press PgDn button

Expected Behavior

User scrolls a page down inside the text area

Actual Behavior

Application shifts left

Environment

• Angular: 8.2.14
• CDK/Material: 8.2.3
• Browser(s): Chrome
• Operating System (e.g. Windows, macOS, Ubuntu): Windows 10, Linux (Ubuntu/Linux Mint)

When pressing 'Page Down' in a textarea inside mat-sidenav-content when mat-sidenav[position] is set to "end" will shift the application left visually. Using mat-sidenav[position="start"] the behavior is fine. I've also noticed the amount of shift seems to be related to the number of characters on the line the cursor ends up on. Also pressing left afterwards will shift the application back to the right a bit.
Opening and closing the sidenav resets the application position.

[crisbeto]

It looks like this is a general issue in Chrome since there are a bunch of results that come up like this: https://stackoverflow.com/questions/17808854/pressing-pageup-while-in-textarea-moves-website-out-of-the-window

I tried playing around with some solutions like making the sidenav display: none while it's closed, but it didn't help.