Clarify palettes bootrom behavior (#576)

Also update DEPLOY.md recomended python version

Co-authored-by: Antonio Vivace <[email protected]>
Co-authored-by: Eldred Habert <[email protected]>

Author: 3 people

DEPLOY.md

@@ -41,7 +41,8 @@ docker build -t pandocs .
 
 If you prefer to install every dependency locally:
 
-1. Install [Rust](https://www.rust-lang.org/tools/install), [mdBook](https://github.com/rust-lang/mdBook#readme), and [Python 3](https://www.python.org/downloads) (3.9 or an earlier version).
+1. Install [Rust](https://www.rust-lang.org/tools/install), [mdBook](https://github.com/rust-lang/mdBook#readme), and [Python 3](https://www.python.org/downloads) (version 3.9 or newer).
+
   mdBook is the tool rendering the documentation, Rust is used for some custom plugins and Python scripts are used to render some images. E.g.:
   ```sh
   # Install Rust using rustup

src/Palettes.md

@@ -89,9 +89,12 @@ color #0 uninitialized.
 
 :::tip NOTE
 
-The boot ROM leaves all object colors uninitialized (and thus somewhat random),
+In CGB mode, the boot ROM leaves all object colors uninitialized (and thus somewhat random/unreliable),
 aside from setting the first byte of OBJ0 color #0 to $00, which is unused.
 
+In DMG compatibility mode, the boot ROM sets the first 2 object palettes which are
+used by OBP0/OBP1, [as explained here](<#Compatibility palettes>).
+
 :::
 
 ### RGB Translation by CGBs