It seems that the issue you're experiencing with strange icon resolution at 150% UI scaling is known and has been discussed in various contexts. The UI scaling can sometimes cause icons to appear blurry or pixelated, especially at non-standard scaling percentages like 150%. This is because the UI elements are typically optimized for 100% or 200% scaling, where the assets are rendered at their intended resolutions.

For the launcher and editor icons, you might want to try setting the UI scale to 200% for the best results, as mentioned in the discussions. This should provide a crisper and more consistent appearance for the icons and other UI elements. If 200% scaling is too large for your preference, you might need to compromise with a slightly less sharp appearance at 150%.

Additionally, you can reset your settings by deleting the prefs.json file in your Spine user folder, which might help if there are any corrupted settings causing the issue.

Here are some relevant links and tips from the discussions:

• Spine Troubleshooting: User files
• Adjusting the interface scale setting via the Settings dialog.
• Using multiples of 100% or 200% for better results.

If the problem persists, it might be worth checking if your GPU drivers are up-to-date or if there are any other software conflicts affecting the UI scaling.