Describe the bug

When applying an inline format to a region of text, any other texts in the same paragraph with that same format appear as highlighted. I would only expect the selected text to be highlighted.

To Reproduce

Steps to reproduce the behavior:

1. Navigate to Posts > Add New
2. Insert a new paragraph block
3. Insert some text
4. Apply bold to a fragment of text
5. Apply bold to an entirely separate fragment of text
6. Observe that both fragments of text are highlighted

Expected behavior

Only the text selected at step 5 should appear as highlighted when bold is applied.

Screenshots

Desktop

• OS: macOS Mojave Version 10.14.3
• Browser: Chrome Version 72.0.3626.119 (Official Build) (64-bit)

Additional context

Gutenberg master (e0adbe0), 5.1.0 latest release.

cc @iseulde