Created attachment 153509 [details]
example of the white trace marks appearing on an added reference image

SUMMARY
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***


STEPS TO REPRODUCE
1. Use the Reference Image tool to add a reference image (any file type) to a Krita document
2. Select any of the following: Freehand Brush Tool, Line Tool, Rectangle Tool, Ellipse Tool, Polygon Tool, Polyline Tool, Dynamic Brush Tool, Multibrush Tool, or Smart Patch Tool
3. Move cursor across canvas without drawing or clicking

OBSERVED RESULT
White trace marks appear wherever cursor is moved across canvas

EXPECTED RESULT
No trace marks should appear

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
The trace marks disappear when the cursor leaves the canvas window, or when another button is pressed, but are intrusive enough to make using the reference tool feature while drawing difficult. Attached is an example screenshot of the marks on a random reference image added using the tool.