Gutenberg How-To Block Lagging When You Get to 15+ Steps

[Jerparx]

Please give us a description of what happened.

When creating a post using the How-To block in Gutenberg, there's a noticeable lag when you get to 15+ steps.

Adding the first few steps is fine:
Video: https://imgur.com/6ipyIGG

But when it reaches 15 or more, it starts to lag.
Video: https://imgur.com/a/1fpNiNd

Please describe what you expected to happen and why.

Shouldn't lag even with 15 or more steps.

How can we reproduce this behavior?

1. Activate Gutenberg
2. Create a new post and use How-To block
3. Add steps and enter step title until you reach 15-20 steps
4. Notice the speed difference when typing the title/description

Technical info

• If relevant, which editor is affected (or editors):

• Gutenberg
• Classic Editor plugin

Used versions

• WordPress version: 4.9.8
• Yoast SEO version: 9.2.1
• Gutenberg plugin version: 4.6.1
• Tested with theme: Twenty Fifteen

[Endda]

Thanks for submitting this issue. The problem gets even worse when adding images to the steps as well.

I've had to click on the next step in the list and wait as long as 45+ seconds until the blinking cursor appears

[afercia]

Related in Gutenberg:

Delay TinyMCE initialisation to focus
WordPress/gutenberg#10723

implemented as first step for:

Try: TinyMCE: On-demand initialization
WordPress/gutenberg#9040