Backspace at beginning of list item may delete entire list in Firefox

Phenomenon

When pressing Backspace at the beginning of a list item in Firefox, the entire list may be deleted or unexpected nested structures may be created. This behavior differs from Chrome, which converts the list item to a paragraph.

Reproduction example

1. Create a list with items: <ul><li>Item 1</li><li>Item 2</li></ul>
2. Place cursor at the very beginning of the first list item
3. Press Backspace

Observed behavior

• The entire list may be deleted
• Or nested list structures may be created unexpectedly
• List items may be converted to paragraphs in an inconsistent way
• DOM structure may become malformed

Expected behavior

• The list item should be deleted while maintaining list structure
• Remaining list items should stay in the list
• Behavior should be consistent with Chrome

Browser Comparison

• Chrome/Edge: Converts list item to paragraph (more predictable)
• Firefox: May delete entire list (this case)
• Safari: May create empty list items

Notes and possible direction for workarounds

• Intercept beforeinput events to prevent default behavior
• Implement custom deletion that maintains list structure
• Check for list context before allowing deletion
• Normalize DOM structure after deletion operations