We haven't made any changes regarding DropDownWidth / Width of RadComboBox. Can you try the page I am sending you?
If the combos behave correctly on this page, can you try to integrate them as is in your project. If they still behave correctly and the other instances do not, well I am out of ideas.
But if the comboboxes break and any moment, can you please record a video of what is showing up and attach it to this thread?
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