diff --git a/frontend/src/components/simulator/CircuitVerificationModal.tsx b/frontend/src/components/simulator/CircuitVerificationModal.tsx
index fb5e7402..3deddafb 100644
--- a/frontend/src/components/simulator/CircuitVerificationModal.tsx
+++ b/frontend/src/components/simulator/CircuitVerificationModal.tsx
@@ -9,6 +9,7 @@
  * The component is dumb: it just renders the verification result it's
  * given. The caller (EditorToolbar) decides when to show it.
  */
+import { createPortal } from 'react-dom';
 import type { CircuitWarning, VerificationResult } from '../../simulation/verify/circuitVerifier';
 
 interface Props {
@@ -24,7 +25,9 @@ const SEVERITY_COPY: Record<CircuitWarning['severity'], { label: string; color:
 
 export const CircuitVerificationModal: React.FC<Props> = ({ result, onCancel, onRunAnyway }) => {
   const items: CircuitWarning[] = [...result.errors, ...result.warnings];
-  return (
+  // Portaled to <body>: see LibraryManagerModal - the toolbar's
+  // container-type would otherwise shrink this fixed overlay.
+  return createPortal(
     <div style={styles.overlay} onClick={onCancel}>
       <div style={styles.modal} onClick={(e) => e.stopPropagation()}>
         <h2 style={styles.title}>Circuit verification</h2>
@@ -62,7 +65,8 @@ export const CircuitVerificationModal: React.FC<Props> = ({ result, onCancel, on
           </button>
         </div>
       </div>
-    </div>
+    </div>,
+    document.body,
   );
 };
 
diff --git a/frontend/src/components/simulator/InstallLibrariesModal.tsx b/frontend/src/components/simulator/InstallLibrariesModal.tsx
index d8c82070..dcd7b318 100644
--- a/frontend/src/components/simulator/InstallLibrariesModal.tsx
+++ b/frontend/src/components/simulator/InstallLibrariesModal.tsx
@@ -1,4 +1,5 @@
 import React, { useState, useCallback } from 'react';
+import { createPortal } from 'react-dom';
 import { useTranslation } from 'react-i18next';
 import { installLibrary } from '../../services/libraryService';
 import { useSimulatorStore } from '../../store/useSimulatorStore';
@@ -129,7 +130,10 @@ export const InstallLibrariesModal: React.FC<InstallLibrariesModalProps> = ({
   const installedCount = items.filter((i) => i.status === 'done').length;
   const allDone = items.length > 0 && pendingCount === 0 && !running;
 
-  return (
+  // Portaled to <body>: the toolbar ancestor has container-type
+  // (container queries), which turns it into the containing block for
+  // position:fixed and shrank the overlay to the toolbar's box.
+  return createPortal(
     <div className="ilib-overlay" onClick={running ? undefined : onClose}>
       <div className="ilib-modal" onClick={(e) => e.stopPropagation()}>
         {/* Header */}
@@ -280,6 +284,7 @@ export const InstallLibrariesModal: React.FC<InstallLibrariesModalProps> = ({
           )}
         </div>
       </div>
-    </div>
+    </div>,
+    document.body,
   );
 };
diff --git a/frontend/src/components/simulator/LibraryManagerModal.css b/frontend/src/components/simulator/LibraryManagerModal.css
index 5737db89..e88db751 100644
--- a/frontend/src/components/simulator/LibraryManagerModal.css
+++ b/frontend/src/components/simulator/LibraryManagerModal.css
@@ -28,7 +28,10 @@
   border-radius: 8px;
   width: 680px;
   max-width: 95vw;
-  max-height: 80vh;
+  /* Fixed tall height (not just a cap): the list is the modal's whole
+     point, so give it the room instead of jumping sizes per search. */
+  height: min(86vh, 1000px);
+  max-height: 92vh;
   display: flex;
   flex-direction: column;
   box-shadow: 0 24px 64px rgba(0, 0, 0, 0.6);
diff --git a/frontend/src/components/simulator/LibraryManagerModal.tsx b/frontend/src/components/simulator/LibraryManagerModal.tsx
index 97df229b..14c3adf6 100644
--- a/frontend/src/components/simulator/LibraryManagerModal.tsx
+++ b/frontend/src/components/simulator/LibraryManagerModal.tsx
@@ -1,4 +1,5 @@
 import React, { useState, useEffect, useCallback, useRef, useMemo } from 'react';
+import { createPortal } from 'react-dom';
 import { useTranslation } from 'react-i18next';
 import {
   searchLibraries,
@@ -279,7 +280,10 @@ export const LibraryManagerModal: React.FC<LibraryManagerModalProps> = ({ isOpen
   if (!isOpen) return null;
   const browsing = !searchQuery.trim();
 
-  return (
+  // Portaled to <body>: the toolbar ancestor has container-type
+  // (container queries), which turns it into the containing block for
+  // position:fixed and shrank the overlay to the toolbar's box.
+  return createPortal(
     <div className="lib-modal-overlay" onClick={onClose}>
       <div className="lib-modal" onClick={(e) => e.stopPropagation()}>
         {/* Header — the pro custom-upload button injects into .lib-modal-header */}
@@ -459,6 +463,7 @@ export const LibraryManagerModal: React.FC<LibraryManagerModalProps> = ({ isOpen
           </div>
         </div>
       </div>
-    </div>
+    </div>,
+    document.body,
   );
 };