824ce64e66
there is existing handler-code at e.g. https://github.com/spesmilo/electrum/blob/1a7634e615156f6f9b4f799e0d549af05446bc69/electrum/gui/qt/transaction_dialog.py#L309 but we should make sure setData() always raises the exc when needed, as paintEvent() is too late for nice handling. closes https://github.com/spesmilo/electrum/issues/4288 closes https://github.com/spesmilo/electrum/issues/4280