Inconsistent Home/End Key Navigation Around Lines Beginning Or Ending With OMath Objects

[brichwin]

Description

When using Home/End keys to navigate lines containing OMath objects in Word 365 (macOS/Windows), the cursor behavior is inconsistent and can unexpectedly leave screen reader users inside the Equation Editor (without clear indication), potentially causing unintended math expression modifications and an improperly formatted document. This issue affects both macOS and Windows versions of Word 365.

A video demonstrating the issue is available: Video: Inconsistent Home/End Key Navigation Around Lines Beginning Or Ending With OMath Objects (3 minutes)

Expected Behavior

• Home key should always move cursor to the absolute beginning of the line
• End key should always move cursor to the absolute end of the line
• Single key press should complete the navigation without getting trapped in Equation Editor

Actual Behavior

1. Lines ending with OMath: Not Working as expected

   • Home (works correctly)
     • Moves to line start
   • End
     • Stops at end of math expression inside Equation Editor
     • Requires second End key press or right arrow to reach true line end

2. Lines starting with OMath: Not Working as expected

   • Home
     • Stops at start of math expression inside Equation Editor
     • Requires second Home key press or left arrow to reach true line start
   • End (works correctly)
     • Moves to line end

3. Lines with only text: Working as expected

   • Home
     • Moves to line start
   • End
     • Moves to line end

4. Lines with text + OMath + text: Working as expected

   • Home
     • Moves to line start
   • End
     • Moves to line end

Impact

Note: This behavior particularly affects non-visual users.

1. Screen reader users have no indication they're inside of the Equation Editor
2. Users may inadvertently modify math expressions when intending to add text to the line
3. Requires additional keystrokes, reducing efficiency
4. Creates inconsistent navigation experience

Steps to Reproduce

1. Create a Word document with these test cases:

   This is a regular text line.
   This is text before math: $A \cup B$. This is text after math.
   This is text followed by math: $A \cup B$
   $A \cup B$ This is text after starting math.
   

   Alternately, use this sample word file: Test File for End Key Bug When Line Ends in an OMath Object.docx
2. Place cursor in each line and test Home/End key navigation
3. Note behavior differences, especially when OMath objects start or end the line

Suggested Fix

Modify the Home/End key behavior to:

1. Always navigate to absolute line boundaries in a single key press
2. Skip over Equation Editor activation when using Home/End navigation
3. Provide clear indication (via screen reader) when cursor enters Equation Editor. See No Audible Announcement of When the Equation Editor Appears or Disappears When Editing a Document with a Screen Reader #27

Tested Version Information

Windows OS

OS Version:
-- OS Name: Microsoft Windows 11 Enterprise
-- Version: 10.0.22621 Build 22621
-- Locale: United States
Microsoft Word Version:
-- Microsoft 365 Apps for enterprise
-- Version 2402 (Build 17328.20612 Click-to-Run) Semi-Annual Enterprise Channel

macOS

OS Version:
-- Sonoma 14.6.1
Microsoft Word Version:
-- License: Microsoft 365 Subscription
-- Version 16.90.2 (24102719)