docs: enable tmux true color and italic guide

README.md

@@ -1425,6 +1425,14 @@ Full list of support terminals can be found here: <https://github.com/termstanda
 
 Full list of Unsupported terminals can be found here: <https://github.com/termstandard/colors#not-supporting-truecolor>
 
+### FOR TMUX USERS
+
+FOLLOW THESE GIST BEFORE OPENING THE ISSUE
+
+- [Enable true color support](https://gist.github.com/andersevenrud/015e61af2fd264371032763d4ed965b6) to fix the [abnormal colors](https://github.com/catppuccin/nvim/issues/415)
+
+- [Enable italic font support](https://gist.github.com/gyribeiro/4192af1aced7a1b555df06bd3781a722) to fix the [incorrect if, then, else, end highlights](https://github.com/catppuccin/nvim/issues/428)
+
 # Thanks to
 
 - [Pocco81](https://github.com/Pocco81)