Mouse and Keyboard Text Selection Visually Broken in STS on macOS

[AmoghavarshaKM10]

Problem Description

Text selection in the STS editor is functionally working but visually broken. When attempting to select multiple lines of code, the selection appears to only highlight a single line visually, but all intended lines are actually selected and can be copied/pasted. This affects both mouse/trackpad dragging and keyboard selection methods.

Steps to Reproduce
Launch Spring Tool Suite on MacBook Air M4

Open any Java file containing multiple lines of code (10+ lines)

Attempt to select multiple lines using either:

Click and drag with trackpad or mouse

Use keyboard: Position cursor at start, hold Shift and use Arrow keys

Observe visual result: Only one line shows selection highlight

Verify functional selection: Press Cmd+C to copy, paste into another application - note all intended lines were copied

The visual feedback does not match the actual selection range

Troubleshooting Already Attempted

• ✅ Complete uninstall and reinstall of STS (multiple times)
• ✅ Tested with both Apple trackpad and external USB mouse
• ✅ Reset all STS preferences to factory defaults
• ✅ Launched STS with -clean flag
• ✅ Deleted workspace .metadata folder completely
• ✅ Removed all STS configuration files from ~/Library/Application Support/
• ✅ Tested with various graphics VM arguments:
  • -Dsun.java2d.opengl=true/false
  • -Dsun.java2d.noddraw=true
  • -Dswt.autoScale=100
• ✅ Reset macOS mouse and trackpad settings to defaults
• ✅ Verified Accessibility and Input Monitoring permissions
• ✅ Confirmed the issue is isolated to STS - all other applications (VS Code, IntelliJ, TextEdit, Notes, Safari) work normally
• ✅ Tested with standard Eclipse IDE for comparison
• ✅ Removed all external mouse configurations from system
• ✅ Restarted macOS multiple times
• ✅ Created new user account on macOS - issue persists system-wide
• ✅ Tried both Dark and Light themes in STS
• ✅ Tested with different file types (.java, .xml, .txt, .properties)

Critical Observations:

The issue is 100% reproducible across all file types and projects

Selection functionally works - the problem is purely visual rendering

Copy/paste, cut, and delete operations work correctly on the full selection

No error messages appear in console logs during selection attempts

Issue persists across complete reinstalls and different workspaces

Both built-in trackpad and external mice exhibit the same behavior

The problem began immediately after fresh installation on M4 MacBook Air

[martinlippert]

You probably updated to macOS 26.1, which breaks the selection highlighting in Eclipse 2025-09 and therefore Spring Tools for Eclipse 4.37.

See:

• https://bsky.app/profile/springtools.bsky.social/post/3m4urjw6p6k2v
• https://x.com/springtools4/status/1986010622329233496

The underlying Eclipse bug is:
eclipse-platform/eclipse.platform.swt#2621

At the moment, we recommend to grab an early snapshot build of Spring Tools 5 for Eclipse 4.38 milestone builds from https://cdn.spring.io/spring-tools/snapshot/nightly-distributions.html, which has the fix included already.

These builds are snapshot builds, so there might be rough edges or things that need work. If you come across one of those rough edges, please let us know, so that we can get those fixed as soon as possible.

[martinlippert]

We added a workaround for a patch release 4.32.2. Stay tuned.

[navy1978]

thanks for this ;)

[AmoghavarshaKM10]

thank you!!