diff --git a/buildroot/share/git/mfdoc b/buildroot/share/git/mfdoc
index 9a69b93cca85..2ffaacc11866 100755
--- a/buildroot/share/git/mfdoc
+++ b/buildroot/share/git/mfdoc
@@ -4,14 +4,29 @@
 #
 # Start Jekyll in watch mode to work on Marlin Documentation and preview locally
 #
+# Usage: mfdoc [--host HOST] [--port PORT]
+#
 
 TEST=0
-case "$1" in
-  -t) TEST=1; shift ;;
-  "") ;;
-  *) echo "Usage: `basename $0` [-t]" 1>&2 ; exit 1 ;;
-esac
-[[ $# == 0 ]] || { echo "Usage: `basename $0` [-t]" 1>&2 ; exit 1; }
+HOST="127.0.0.1"
+PORT="4000"
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+        -t) TEST=1; shift ;;
+    --test) TEST=1; shift ;;
+    --host) shift; HOST="$1"; shift ;;
+    --port) shift; PORT="$1"; shift ;;
+    --help)
+      echo "Usage: `basename $0` [--test] [--host HOST] [--port PORT]"
+      exit 0
+      ;;
+    *)
+      echo "Usage: `basename $0` [--test] [--host HOST] [--port PORT]" 1>&2
+      exit 1
+      ;;
+  esac
+done
 
 MFINFO=$(mfinfo) || exit 1
 IFS=' ' read -a INFO <<< "$MFINFO"
@@ -22,7 +37,7 @@ BRANCH=${INFO[5]}
 [[ $ORG == "MarlinFirmware" && $REPO == "MarlinDocumentation" ]] || { echo "Wrong repository." 1>&2; exit 1; }
 
 opensite() {
-  URL="http://127.0.0.1:4000/"
+  URL="http://$HOST:$PORT/"
   OPEN=$( which gnome-open xdg-open open | head -n1 )
   if [ -z "$OPEN" ]; then
     echo "Can't find a tool to open the URL:"
@@ -40,7 +55,7 @@ fi
 
 echo "Previewing MarlinDocumentation..."
 
-bundle exec jekyll serve --watch --incremental | {
+bundle exec jekyll serve --host "$HOST" --port "$PORT" --watch --incremental | {
   while IFS= read -r line
   do
     [[ $line =~ "Server running" ]] && opensite
diff --git a/buildroot/share/git/mfinfo b/buildroot/share/git/mfinfo
index 85d486971f56..20f6a5aa8554 100755
--- a/buildroot/share/git/mfinfo
+++ b/buildroot/share/git/mfinfo
@@ -58,6 +58,7 @@ case "$REPO" in
           Marlin ) TARG=bugfix-2.1.x ; ((INDEX == 1)) && TARG=bugfix-1.1.x ; [[ $BRANCH =~ ^[12]$ ]] && USAGE=1 ;;
   Configurations ) TARG=import-2.1.x ;;
     MarlinBuilds ) TARG=main ;;
+         Marlin3 ) TARG=dev ;;
                * ) TARG=master ;;
 esac
 
diff --git a/buildroot/share/git/mfrb b/buildroot/share/git/mfrb
index b55a34e0100d..4bd3f5390b48 100755
--- a/buildroot/share/git/mfrb
+++ b/buildroot/share/git/mfrb
@@ -1,8 +1,11 @@
 #!/usr/bin/env bash
 #
 # mfrb
+# MF Rebase manually to re-message, merge, drop, etc.
 #
-# Do "git rebase -i" against the repo's "target" branch
+# Does "git rebase -i" against the repo's "target" branch
+#
+# Usually `git rebase -i upstream/bugfix-2.1.x`
 #
 
 MFINFO=$(mfinfo "$@") || exit 1