Update README.md

Moved instructions into Firefox section

README.md

@@ -64,7 +64,7 @@ Feel free to add your distributions package in an issue/PR.
 
 ## Building
 
-You'll need `meson`, `ffmpeg` with vaapi enabled, the `gstreamer-plugins-bad` library, and [`nv-codec-headers`](https://git.videolan.org/?p=ffmpeg/nv-codec-headers.git) installed.
+You'll need `meson`, the `gstreamer-plugins-bad` library, and [`nv-codec-headers`](https://git.videolan.org/?p=ffmpeg/nv-codec-headers.git) installed.
 
 | Package manager | Packages                                        | Optional packages for additional codec support |
 |-----------------|-------------------------------------------------|------------------------------------------------|
@@ -103,7 +103,7 @@ Environment variables used to control the behavior of this library.
 
 ## Firefox
 
-To use the driver with firefox you will need at least Firefox 96, the following config options need to be set in the `about:config` page:
+To use the driver with firefox you will need at least Firefox 96, `ffmpeg` compiled with vaapi support (search ffmpeg output for --enable-vaapi), and the following config options need to be set in the `about:config` page:
 
 | Option | Value | Reason |
 |---|---|---|