diff --git a/.gdbinit b/.gdbinit
index 56bdc4dcd765..8d0a71fd3184 100644
--- a/.gdbinit
+++ b/.gdbinit
@@ -187,8 +187,16 @@ define ft
   call $arg0->DumpFrameTree()
 end
 
+define ftp
+  call $arg0->DumpFrameTreeInCSSPixels()
+end
+
 define ftl
   call $arg0->DumpFrameTreeLimited()
 end
 
+define ftlp
+  call $arg0->DumpFrameTreeLimitedInCSSPixels()
+end
+
 source .gdbinit_python
diff --git a/layout/generic/nsFrame.cpp b/layout/generic/nsFrame.cpp
index 63dfab70acfc..c982ac7f0d3e 100644
--- a/layout/generic/nsFrame.cpp
+++ b/layout/generic/nsFrame.cpp
@@ -8243,7 +8243,14 @@ void nsIFrame::DumpFrameTree() const {
   PresShell()->GetRootFrame()->List(stderr);
 }
 
+void nsIFrame::DumpFrameTreeInCSSPixels() const {
+  PresShell()->GetRootFrame()->List(stderr, "", ListFlag::DisplayInCSSPixels);
+}
+
 void nsIFrame::DumpFrameTreeLimited() const { List(stderr); }
+void nsIFrame::DumpFrameTreeLimitedInCSSPixels() const {
+  List(stderr, "", ListFlag::DisplayInCSSPixels);
+}
 
 #endif
 
diff --git a/layout/generic/nsIFrame.h b/layout/generic/nsIFrame.h
index 3831cf37bb01..06d27e826750 100644
--- a/layout/generic/nsIFrame.h
+++ b/layout/generic/nsIFrame.h
@@ -4762,11 +4762,13 @@ class nsIFrame : public nsQueryFrame {
    * Dump the frame tree beginning from the root frame.
    */
   void DumpFrameTree() const;
+  void DumpFrameTreeInCSSPixels() const;
 
   /**
    * Dump the frame tree beginning from ourselves.
    */
   void DumpFrameTreeLimited() const;
+  void DumpFrameTreeLimitedInCSSPixels() const;
 
   virtual nsresult GetFrameName(nsAString& aResult) const = 0;
 #endif
diff --git a/python/lldbutils/lldbutils/layout.py b/python/lldbutils/lldbutils/layout.py
index 9a12199bec21..0f2b3a96a461 100644
--- a/python/lldbutils/lldbutils/layout.py
+++ b/python/lldbutils/lldbutils/layout.py
@@ -9,11 +9,22 @@ def frametree(debugger, command, result, dict):
     debugger.HandleCommand('expr (' + command + ')->DumpFrameTree()')
 
 
+def frametree_pixels(debugger, command, result, dict):
+    """Dumps the frame tree containing the given nsIFrame* in CSS pixels."""
+    debugger.HandleCommand('expr (' + command + ')->DumpFrameTreeInCSSPixels()')
+
+
 def frametreelimited(debugger, command, result, dict):
     """Dumps the subtree of a frame tree rooted at the given nsIFrame*."""
     debugger.HandleCommand('expr (' + command + ')->DumpFrameTreeLimited()')
 
 
+def frametreelimited_pixels(debugger, command, result, dict):
+    """Dumps the subtree of a frame tree rooted at the given nsIFrame*
+    in CSS pixels."""
+    debugger.HandleCommand('expr (' + command + ')->DumpFrameTreeLimitedInCSSPixels()')
+
+
 def pstate(debugger, command, result, dict):
     """Displays a frame's state bits symbolically."""
     debugger.HandleCommand('expr mozilla::PrintFrameState(' + command + ')')
@@ -21,9 +32,16 @@ def pstate(debugger, command, result, dict):
 
 def init(debugger):
     debugger.HandleCommand('command script add -f lldbutils.layout.frametree frametree')
+    debugger.HandleCommand(
+        'command script add -f lldbutils.layout.frametree_pixels frametree_pixels')
     debugger.HandleCommand(
         "command script add -f lldbutils.layout.frametreelimited frametreelimited"
     )
+    debugger.HandleCommand(
+        "command script add -f lldbutils.layout.frametreelimited_pixels frametreelimited_pixels"
+    )
     debugger.HandleCommand('command alias ft frametree')
+    debugger.HandleCommand('command alias ftp frametree_pixels')
     debugger.HandleCommand('command alias ftl frametreelimited')
+    debugger.HandleCommand('command alias ftlp frametreelimited_pixels')
     debugger.HandleCommand('command script add -f lldbutils.layout.pstate pstate')