When the screen width is not large enough, the blocks toolbars can exceed the editor's container

[JustinyAhin]

This was reported by a user during a contributor day at Yoast on April 9.

Description

When the screen width is not large enough, the blocks toolbars can exceed the editor's container.
This happens for instance when both the inserter panel and the block options panel are opened, and the block is near the right side of the screen.

Step-by-step reproduction instructions

1. Create a new page / post
2. Add a three columns block
3. In the third column, add a paragraph, an image or a button block

Expected behaviour

The block toolbar should be inside the editor container

Actual behaviour

The block toolbar exceed the editor's container

Screenshots or screen recording (optional)

WordPress information

• WordPress version: 5.7
• Gutenberg version: 10.3.2
• Are all plugins except Gutenberg deactivated? Yes
• Are you using a default theme (e.g. Twenty Twenty-One)?Yes

Device information

• Device: MacBook Pro
• Operating system: macOS 11.3
• Browser: Firefox Developer Edition 88.0b9 (64 bits)

[annezazu]

Thanks for opening :) Closing this though as it's already been reported here! #30398