I have a similiar problem with the header as stated here: Modules not visible in header - #2 by Jay.
I exported the app from retool Cloud version to my on-prem version. Now the header is visible but components inside the header are missing (which existed on the cloud version) and I cant drag&drop any components on the header:
@Jay may be a feature flag missing? Thanks
Yes! This is a feature flag. I can turn that on for you. You would have to provide some information so that we can find your license key (the last 4 of your license key for example), which I understand you might not want to provide in a public forum. You can write into our chat inside of your app (bottom right corner) and we can help you with that. Or you can email at email@example.com.
Hope to get this solved for you soon!