Thanks for letting us know. If I understand correctly, this one is already on the radar and the developers will be working on this soon.
However, in the Dark Theme, the text in the Title Bars of Cues in the script is white. This does make it difficult to see when the cue Colors are also light, such as the default color for Comments. If this is what you are seeing, until we can address this, you can change the color of any Cue type (including Comments) to make the white text more noticeable.
Go to Settings>General Settings>Script. From here you can change the color of your Cue Title Bars.