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Windows 10, Delphi 10.2 Tokyo, Firemonkey framework.
I drop a TCombobox on the form, populate it with 20000 items (takes 5 seconds), then when I click the arrow of the combobox for the dropdown to appear, it takes 15 seconds to do so. The VCL TComboBox does this instantly for me.
Is there anything I can do to speed up this behavior? Why does it take that long?