diff --git a/devtools/client/memory/components/census-tree-item.js b/devtools/client/memory/components/census-tree-item.js
index a9f94a6f840f..c5d08cefcebe 100644
--- a/devtools/client/memory/components/census-tree-item.js
+++ b/devtools/client/memory/components/census-tree-item.js
@@ -98,7 +98,7 @@ const CensusTreeItem = module.exports = createClass({
       dom.span(
         {
           className: "heap-tree-item-field heap-tree-item-name",
-          style: { marginLeft: depth * TREE_ROW_HEIGHT }
+          style: { marginInlineStart: depth * TREE_ROW_HEIGHT }
         },
         arrow,
         pointer,
diff --git a/devtools/client/memory/components/dominator-tree-item.js b/devtools/client/memory/components/dominator-tree-item.js
index 13a8d3ce07e8..bf76ee9b44bf 100644
--- a/devtools/client/memory/components/dominator-tree-item.js
+++ b/devtools/client/memory/components/dominator-tree-item.js
@@ -130,7 +130,7 @@ const DominatorTreeItem = module.exports = createClass({
       dom.span(
         {
           className: "heap-tree-item-field heap-tree-item-name",
-          style: { marginLeft: depth * TREE_ROW_HEIGHT }
+          style: { marginInlineStart: depth * TREE_ROW_HEIGHT }
         },
         arrow,
         label,
diff --git a/devtools/client/memory/components/dominator-tree.js b/devtools/client/memory/components/dominator-tree.js
index a8c7c95d93d7..a1105a4fc541 100644
--- a/devtools/client/memory/components/dominator-tree.js
+++ b/devtools/client/memory/components/dominator-tree.js
@@ -45,7 +45,7 @@ const DominatorTreeSubtreeFetching = createFactory(createClass({
       dom.span({ className: "heap-tree-item-field heap-tree-item-bytes" }),
       dom.span({
         className: "heap-tree-item-field heap-tree-item-name devtools-throbber",
-        style: { marginLeft: depth * TREE_ROW_HEIGHT }
+        style: { marginInlineStart: depth * TREE_ROW_HEIGHT }
       })
     );
   }
@@ -87,7 +87,7 @@ const DominatorTreeSiblingLink = createFactory(createClass({
       dom.span(
         {
           className: "heap-tree-item-field heap-tree-item-name",
-          style: { marginLeft: depth * TREE_ROW_HEIGHT }
+          style: { marginInlineStart: depth * TREE_ROW_HEIGHT }
         },
         dom.a(
           {
diff --git a/devtools/client/memory/test/browser/browser_memory_no_auto_expand.js b/devtools/client/memory/test/browser/browser_memory_no_auto_expand.js
index ce3c8fa94439..ffd481c744d5 100644
--- a/devtools/client/memory/test/browser/browser_memory_no_auto_expand.js
+++ b/devtools/client/memory/test/browser/browser_memory_no_auto_expand.js
@@ -31,7 +31,7 @@ this.test = makeMemoryTest(TEST_URL, function* ({ tab, panel }) {
 
   for (let el of nameElems) {
     dumpn(`Found ${el.textContent.trim()}`);
-    is(el.style.marginLeft, "0px",
+    is(el.style.marginInlineStart, "0px",
        "None of the elements should be an indented/expanded child");
   }
 });