selecting and replacing a series of spans gives null range crash, with corrupted content

[rblaa]

When selecting and deleting a range of spans with new text, there is a null pointer crash that loses the cursor, leaves the html content slightly corrupted.

Steps for Reproduction

1. Edit an html fragment with spans like:

<p><strong>Project Status</strong>: <span style="color: green">Green</span> / <span style="color: yellow">Yellow</span> / <span style="color: red">Red</span>
</p>

2. Select the spans, e.g. from "Green" till the end of line at "Red", start typing some replacement text, e.g. say "ok!".

Expected behavior:
Green / Yellow / Red disappears and is replaced by the new text, giving, e.g.

<p><strong>Project Status</strong>: ok!
</p>

Actual behavior:

• Cursor disappears
• Clicking with the mouse restores the cursor, newly typed text is in bold
• Often I cannot unbold the "Project Status" part
• Often find corrupted content, e.g. an extra </strong> tag that messes up further display of the html content.

Platforms:
Mac OS 10.14.2

Version:
Quill 1.3.6

[luin]

Fixed in #3807. Feel free to let me know if there is anything missing. Closing