diff --git a/app/assets/javascripts/merge_request_tabs.js b/app/assets/javascripts/merge_request_tabs.js
index 03f3bb42193..2950c2299ab 100644
--- a/app/assets/javascripts/merge_request_tabs.js
+++ b/app/assets/javascripts/merge_request_tabs.js
@@ -419,7 +419,7 @@ export default class MergeRequestTabs {
     if (this.diffViewType() === 'parallel' || removeLimited) {
       $wrapper.removeClass('container-limited');
     } else {
-      $wrapper.addClass('container-limited');
+      $wrapper.toggleClass('container-limited', this.fixedLayoutPref);
     }
   }
 
diff --git a/changelogs/unreleased/mr-file-tree-inline-fluid-width-fix.yml b/changelogs/unreleased/mr-file-tree-inline-fluid-width-fix.yml
new file mode 100644
index 00000000000..b61f47724fc
--- /dev/null
+++ b/changelogs/unreleased/mr-file-tree-inline-fluid-width-fix.yml
@@ -0,0 +1,5 @@
+---
+title: Fixed merge request fill tree toggling not respecting fluid width preference
+merge_request:
+author:
+type: fixed
diff --git a/spec/javascripts/merge_request_tabs_spec.js b/spec/javascripts/merge_request_tabs_spec.js
index 7251ce19a90..7714197c821 100644
--- a/spec/javascripts/merge_request_tabs_spec.js
+++ b/spec/javascripts/merge_request_tabs_spec.js
@@ -224,6 +224,14 @@ describe('MergeRequestTabs', function() {
       expect($('.content-wrapper')).not.toContainElement('.container-limited');
     });
 
+    it('does not add container-limited when fluid layout is prefered', function() {
+      $('.content-wrapper .container-fluid').removeClass('container-limited');
+
+      this.class.expandViewContainer(false);
+
+      expect($('.content-wrapper')).not.toContainElement('.container-limited');
+    });
+
     it('does remove container-limited from breadcrumbs', function() {
       $('.container-limited').addClass('breadcrumbs');
       this.class.expandViewContainer();