I can type above the line but nothing appears for any search I perform. I was trying to add Hubitat Package Manager app and the Echo Speaks app but nothing comes up on anything I type. All I can do is hit done. Reading the readme for package manager, I should see the following screen when I click add user app and type in Hubitat Package Manager:
The search field is only for searching among ones you already installed. You have to actually download and install the Hubitat Package Manager. I don't have it myself as I find it easier to install the user apps I want manually.