In Designer, when 2 mlapp files are open, I receive a Undefined function 'bringToFront' for input arguments of type 'double' error.

I have a GUI app that opens a seperate window with 2 separate .mlapp files, very similar to the Pass Data Between Apps example project (files MainAppExample.mlapp & DialogAppExample.mlapp).

When I have both files open and run the main app, I receive this error:

Undefined function 'bringToFront' for input arguments of type 'double'.
Error in matlab.ui.internal.controller.platformhost.CEFFigurePlatformHost/toFront (line 182)
bringToFront(this.CEF);
Error in matlab.ui.internal.controller.FigureController/toFront (line 480)
toFront(this.PlatformHost);

After debugging, I found it crashes at this line:

figure(1);

If I close the DialogAppExample.mlapp file in my project, it runs without issue. How can I solve this issue?

Also, should I be loading both .mlapp files when I open this project? I am loading them seperately because I couldn't figure out how to have them both load upon startup (similar to the example project 'Pass Data Between Apps')

[Walter Roberson]

The implementing code for that appears to be

toolbox/matlab/uitools/uicomponents/components/+matlab/+ui/+internal/+controller/+platformhost/CEFFigurePlatformHost.m

I will need to look at the source to see if I get any ideas.