Small OpenGL color difference between standalone app and plugin (macOS)

Hi, we have software that builds as a Juce Standalone application and also as Juce AAX and AU plugins, all for macOS. We have a GUI component subclassing juce::OpenGLAppComponent that draws a visualization using OpenGL. We have found slight color differences between the visualization rendered by the standalone app vs the AAX plugin hosted in Pro Tools vs the AU plugin hosted by Logic Pro. For example, the color RGB = (0.5, 0, 0) renders, as measured by the macOS Digital Color Meter (using “Display in Generic RGB” mode), as (121, 0, 0) in the standalone app and (128, 0, 0) in the AAX plugin. The delta between the two rendered colors is different at different intensities. We do not see similar differences in other non-OpenGL parts of the plugin GUI. In our application this small discrepancy can make a difference as we are presenting graphical representations of audio and some quiet sounds get lost in the visualization when the color is not represented correctly.

Does anyone know what might account for these differences? Do applications declare some color space or reference that might be different, say, between Pro Tools and Juce standalone applications? Are there OpenGL defaults that may be somehow different in the standalone app vs Pro Tools vs Logic? I’m really at a loss.