After installing papirus theme, these icons inside Qt Designer got messed up. See pictures.
Original version:


@phidrho Please send bugreport to Qt devs, because program used wrong icons for UI.
If available icon designer on system icon theme - this icons will be replaced:
i'm remove qt4logo icon for solve this, but it's wrong way...
I reported your proposal for solution, bugreport already exists.
bug report
@phidrho Sorry, my fault... really icon designer replaced some toolbar icons. Now this fixed and check.
Anyway this upstream bug. Maybe this happened because used similar icon names for icons (designer-widget-tool), but this strange for editform
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I reported your proposal for solution, bugreport already exists.
bug report