Plugin works in TUI not GUI

I recently installed the plugin txtfmt and used it successfully in Vim TUI mode.

It is activated with the command :set ft=txtfmt. Then, to highlight a region, you enter \h, then it prompts you for a color.

I can confirm the installation in Gvim was successful with the command :MakeTestPage.

For some reason, :set ft=txtfmt has not returned the expected confirmation message, and appears to do nothing.

Could anyone shed light on why this might be?

Thank you very much,

Julius

--
--
You received this message from the "vim_use" maillist.
Do not top-post! Type your reply below the text you are replying to.
For more information, visit http://www.vim.org/maillist.php

---
You received this message because you are subscribed to the Google Groups "vim_use" group.
To unsubscribe from this group and stop receiving emails from it, send an email to vim_use+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/vim_use/CAGrXgp3kBFOObs0tgwV%3D_44UbJi39MjRd%2BfnPdpAxMFQ7_dDSQ%40mail.gmail.com.