Highlight text: Content is marked as modified after selecting text

[fluiddot]

Description

The content of a post is modified after selecting text with color.

Step-by-step reproduction instructions

1. Open the iOS app (NOTE: On Android this can also be reproduced but it's easier to test on iOS).
2. Create a post.
3. Type some text in the first Paragraph block.
4. Save the post.
5. Select the text and tap in the 💧 format button located at the bottom.
6. Choose a color and dismiss the bottom sheet.
7. Save the post.
8. Select the text again.
9. Observe that the Update button located at the top-right corner gets active (i.e. the content was modified).

Expected behaviour

The post content should remain unmodified after selecting any text.

Actual behaviour

The post content is marked as modified unexpectedly after selecting text.

Screenshots or screen recording (optional)

ios-content-modiied-after-selecting-text.mp4

WordPress information

• WordPress version: N/A
• Gutenberg version: N/A
• Are all plugins except Gutenberg deactivated? N/A
• Are you using a default theme (e.g. Twenty Twenty-One)? No, I'm using the Byrne theme.

Device information

• Device: iPhone 15 (simulator)
• Operating system: iOS 17.0
• WordPress app version: 23.8