Editor: Block Inserter doesn't show up on a new line

[hacchism]

Quick summary

As #2 in this support guide explains, we should see a block inserter when on a new line, but it currently doesn't show up.

Steps to reproduce

1. Open an editor.
2. On a new line, check if you can see the + Block Inserter at the side of an empty block.

What you expected to happen

See the + Block Inserter at the side of an empty block.

What actually happened

The + Block Inserter doesn't show up.

Impact

Most (> 50%)

Available workarounds?

Yes, easy to implement

If the above answer is "Yes...", outline the workaround.

There are several other ways to add a new block as explained in https://wordpress.com/support/wordpress-editor/add-content-blocks/#how-to-add-a-block.

Platform (Simple and/or Atomic)

Simple, Atomic

Logs or notes

No response

[Robertght]

📌 REPRODUCTION RESULTS

• Tested on Simple – Replicated
• Tested on Atomic – Replicated
• Replicable outside of Dotcom – No

📌 FINDINGS/SCREENSHOTS/VIDEO This is not happening on self-hosted

📌 ACTIONS

• Triaged
• Raised priority and set it as a Blocker.

[dsas]

Opened https://github.com/WordPress/gutenberg/issues/66632 upstream