This issue seems to be across all apps: It appears that when I select Bold Dark theme for the app (any app), the text does not appear when you type in the search bar (on screens where a search bar has been added). For all of the other themes, the text in the search bar is visible when you begin typing.
Do you mind sharing a link to the app, and are you sure you have the search component activated ?
Don’t hesistate to share screenshots too 
I’ve attached a gif that shows me toggling through the three dark views. You will see when I type something in the search bar, it appears both in both the Dark + Pure Dark modes, but not in Bold (dark) mode. If you type in Bold (dark) mode, you see nothing, although it will filter.
Here’s the apps link as well: 4aeed.glideapp.io
Maybe it’s your cache? What happend when, while in the bold dark, you input some text?
This happens on mobile as well. I’ve applied this theme to multiple apps, and it happens in all of them…also in multiple browsers. Mind you, this isn’t necessarily a theme I intend to use…but just a flag.
And I should clarify b/c the title of my thread is not entirely accurate…the search bar appears, the text within the search bar does not appear.