What happened to your Roku remote? How old is the magnavox universal compared to your TCL?
Tell us what model TCL you have as well as what model universal remote you have so that we can look up specs for these.
Chances are, you may just need to get a replacement remote for the TV, which is honestly the best option since it'll offer you full compatibility and work like it should with navigating the TV menus and apps.
To get a replacement remote simply search on a site like Amazon for the year or model of your TV and the words Roku TV Remote.
For example, I personally have a TCL 49S405 which is the 50" UHD 4K TCL Roku TV (2017 Model) and to find a replacement remote I type in the search on Amazon: 2017 Roku TV remote. Or TCL Roku...