After ofSystemLoadDialog drawing is suspended

This is with 0.9.0

An ofxDatGuiButtonEvent triggers a system open file dialog:

void ofApp::onOfxDatGuiButtonEvent(ofxDatGuiButtonEvent e) {
    if ( == controls.loadButton) {
        ofFileDialogResult openFileResult = ofSystemLoadDialog("Select a CSV dataset file");
        if (openFileResult.bSuccess) {
            // this draws to an FBO which is drawn in main draw()

After that drawing is not updated. Not the FBO, the overlaid real time stuff in my draw() loop of the datGui sidebar.

If I background the app (click on a different OS window) and go back, then drawing updates return.

Is it a bug ? Is there a trick ?

I also tried moving the call to open into draw(), still has the same issue