diff --git a/client/src/App.tsx b/client/src/App.tsx
index d701443..c1eb545 100644
--- a/client/src/App.tsx
+++ b/client/src/App.tsx
@@ -10,18 +10,10 @@ import '@fontsource/roboto/700.css';
 import './reset.css';
 import './app.css';
 
-type SetTitleType = {setTitle: (string) => void, setSubtitle: (string) => void}
-export const SetTitleContext = React.createContext<SetTitleType>({setTitle: () => {}, setSubtitle: () => {}})
-
 function App() {
-  const [title, setTitle] = useState("")
-  const [subtitle, setSubtitle] = useState("")
-
   return (
     <div className="app">
-      <SetTitleContext.Provider value={{setTitle, setSubtitle}}>
-        <Outlet />
-      </SetTitleContext.Provider>
+      <Outlet />
     </div>
   )
 }
diff --git a/client/src/app.css b/client/src/app.css
index c65b42a..5292e3d 100644
--- a/client/src/app.css
+++ b/client/src/app.css
@@ -35,15 +35,22 @@ code {
 }
 
 .btn {
+  line-height: inherit;
   text-decoration: none;
-  color: var(--clr-primary);
-  background: white;
+  background: var(--clr-primary);
+  color: white;
   display: inline-block;
   border-radius: 0.2em;
-  padding: 0.2em .6em;
+  padding: 0.2rem .6em;
   font-size: 1rem;
   margin: 0 .2em;
   border: 0;
+  cursor: pointer;
+}
+
+.btn-inverted {
+  color: var(--clr-primary);
+  background: white;
 }
 
 .btn-disabled, .btn[disabled] {
@@ -63,7 +70,6 @@ code {
 }
 
 .app-bar {
-  z-index: 1500;
   flex: 0;
   background: var(--clr-primary);
   display: flex;
diff --git a/client/src/components/Button.tsx b/client/src/components/Button.tsx
index 2035744..1f63c77 100644
--- a/client/src/components/Button.tsx
+++ b/client/src/components/Button.tsx
@@ -3,12 +3,13 @@ import { Link, LinkProps } from "react-router-dom";
 
 export interface ButtonProps extends LinkProps {
   disabled?: boolean
+  inverted?: boolean
 }
 
 export function Button(props: ButtonProps) {
   if (props.disabled) {
-    return <span className="btn btn-disabled" {...props}>{props.children}</span>
+    return <span className={`btn btn-disabled ${props.inverted ? 'btn-inverted' : ''}`} {...props}>{props.children}</span>
   } else {
-    return <Link className="btn" {...props}>{props.children}</Link>
+    return <Link className={`btn ${props.inverted ? 'btn-inverted' : ''}`} {...props}>{props.children}</Link>
   }
 }
diff --git a/client/src/components/Level.tsx b/client/src/components/Level.tsx
index 16313bb..b685944 100644
--- a/client/src/components/Level.tsx
+++ b/client/src/components/Level.tsx
@@ -33,13 +33,10 @@ import { Main } from './infoview/main'
 import type { Location } from 'vscode-languageserver-protocol';
 
 import { FontAwesomeIcon } from '@fortawesome/react-fontawesome'
-import { faHome, faArrowRight, faArrowLeft } from '@fortawesome/free-solid-svg-icons'
+import { faHome, faArrowRight, faArrowLeft, faRotateLeft } from '@fortawesome/free-solid-svg-icons'
 
 import { styled, useTheme, Theme, CSSObject } from '@mui/material/styles';
-import { AppBarProps as MuiAppBarProps } from '@mui/material/AppBar';
-import Divider from '@mui/material/Divider';
 import Markdown from './Markdown';
-import { SetTitleContext } from '../App';
 
 import Split from 'react-split'
 
@@ -73,6 +70,40 @@ function Level() {
     introductionPanelRef.current!.scrollTo(0,0)
   }, [levelId])
 
+  React.useEffect(() => {
+    if (!commandLineMode) {
+      // Delete last input attempt from command line
+      editor.executeEdits("command-line", [{
+        range: editor.getSelection(),
+        text: "",
+        forceMoveMarkers: false
+      }]);
+      editor.focus()
+    }
+  }, [commandLineMode])
+
+  const handleUndo = () => {
+    const endPos = editor.getModel().getFullModelRange().getEndPosition()
+    let range
+    console.log(endPos.column)
+    if (endPos.column === 1) {
+      range = monaco.Selection.fromPositions(
+        new monaco.Position(endPos.lineNumber - 1, 1),
+        endPos
+      )
+    } else {
+      range = monaco.Selection.fromPositions(
+        new monaco.Position(endPos.lineNumber, 1),
+        endPos
+      )
+    }
+    editor.executeEdits("undo-button", [{
+      range,
+      text: "",
+      forceMoveMarkers: false
+    }]);
+  }
+
   const connection = React.useContext(ConnectionContext)
 
   const gameInfo = useGetGameInfoQuery()
@@ -103,10 +134,10 @@ function Level() {
         <span className="app-bar-title">
           {levelId && `Level ${levelId}`}{level?.data?.title && `: ${level?.data?.title}`}
         </span>
-        <Button disabled={levelId <= 1}
+        <Button disabled={levelId <= 1} inverted={true}
           to={`/world/${worldId}/level/${levelId - 1}`}
           ><FontAwesomeIcon icon={faArrowLeft} />&nbsp;Previous</Button>
-        <Button disabled={levelId >= gameInfo.data?.worldSize[worldId]}
+        <Button disabled={levelId >= gameInfo.data?.worldSize[worldId]} inverted={true}
           to={`/world/${worldId}/level/${levelId + 1}`}
           >Next&nbsp;<FontAwesomeIcon icon={faArrowRight} /></Button>
       </div>
@@ -125,9 +156,13 @@ function Level() {
         </div>
       </div>
       <div className="info-panel">
-        <FormGroup className="input-mode-switch">
-          <FormControlLabel control={<Switch onChange={(ev) => { setCommandLineMode(!commandLineMode) }} />} label="Editor mode" />
-        </FormGroup>
+        <div className="input-mode-switch">
+          {commandLineMode && <button className="btn" onClick={handleUndo}><FontAwesomeIcon icon={faRotateLeft} /> Undo</button>}
+          <FormGroup>
+            <FormControlLabel control={<Switch onChange={(ev) => { setCommandLineMode(!commandLineMode) }} />} label="Editor mode" />
+          </FormGroup>
+        </div>
+
         <EditorContext.Provider value={editorConnection}>
           <MonacoEditorContext.Provider value={editor}>
             <InputModeContext.Provider value={{commandLineMode, setCommandLineMode}}>
diff --git a/client/src/components/Welcome.tsx b/client/src/components/Welcome.tsx
index 6f36a6f..b9d3f3b 100644
--- a/client/src/components/Welcome.tsx
+++ b/client/src/components/Welcome.tsx
@@ -14,7 +14,6 @@ import { useGetGameInfoQuery } from '../state/api';
 import { Link } from 'react-router-dom';
 import Markdown from './Markdown';
 import { selectCompleted } from '../state/progress';
-import { SetTitleContext } from '../App';
 
 
 function LevelIcon({ worldId, levelId, position }) {
@@ -34,12 +33,9 @@ function Welcome() {
 
   const { nodes, bounds }: any = gameInfo.data ? computeWorldLayout(gameInfo.data?.worlds) : {nodes: []}
 
-  const {setTitle, setSubtitle} = React.useContext(SetTitleContext);
-
   useEffect(() => {
     if (gameInfo.data?.title) {
       window.document.title = gameInfo.data.title
-      setTitle(gameInfo.data.title)
     }
   }, [gameInfo.data?.title])
 
diff --git a/client/src/components/infoview/CommandLine.tsx b/client/src/components/infoview/CommandLine.tsx
index 66432e5..27e6211 100644
--- a/client/src/components/infoview/CommandLine.tsx
+++ b/client/src/components/infoview/CommandLine.tsx
@@ -4,43 +4,67 @@ import { LspDiagnosticsContext } from '../../../../node_modules/lean4-infoview/s
 import { useServerNotificationEffect } from '../../../../node_modules/lean4-infoview/src/infoview/util';
 import * as monaco from 'monaco-editor/esm/vs/editor/editor.api.js'
 import { DiagnosticSeverity, PublishDiagnosticsParams } from 'vscode-languageserver-protocol';
-import { MonacoEditorContext } from '../Level'
+import { InputModeContext, MonacoEditorContext } from '../Level'
 
 import { FontAwesomeIcon } from '@fortawesome/react-fontawesome'
 import { faWandMagicSparkles } from '@fortawesome/free-solid-svg-icons'
 
 
+function hasErrorsOrWarnings(diags) {
+  return diags.some(
+    (d) =>
+      !d.message.startsWith("unsolved goals") &&
+      (d.severity == DiagnosticSeverity.Error || d.severity == DiagnosticSeverity.Warning)
+  )
+}
+
 export function CommandLine() {
 
   const editor = React.useContext(MonacoEditorContext)
   const commandInput = useRef<HTMLInputElement>()
   const [processing, setProcessing] = useState(false)
 
-  // const allDiags = React.useContext(LspDiagnosticsContext)
-  // const fileDiags = allDiags.get(editor.getModel().uri.toString())
+  const { commandLineMode } = React.useContext(InputModeContext)
+  const allDiags = React.useContext(LspDiagnosticsContext)
+  const diags = allDiags.get(editor.getModel().uri.toString())
+
+  React.useEffect(() => {
+    if (hasErrorsOrWarnings(diags)) {
+      // alert("err")
+    }
+  }, [])
 
+  React.useEffect(() => {
+    if (commandLineMode) {
+      const endPos = editor.getModel().getFullModelRange().getEndPosition()
+      if (editor.getModel().getLineContent(endPos.lineNumber).trim() !== "") {
+        editor.executeEdits("command-line", [{
+          range: monaco.Selection.fromPositions(endPos, endPos),
+          text: "\n",
+          forceMoveMarkers: false
+        }]);
+      }
+      editor.setPosition(editor.getModel().getFullModelRange().getEndPosition())
+    }
+  }, [commandLineMode])
 
   const handleSubmit : React.FormEventHandler<HTMLFormElement> = (ev) => {
     ev.preventDefault()
-    var selection = monaco.Selection.fromPositions(
-      editor.getPosition(),
-      editor.getModel().getFullModelRange().getEndPosition()
-    );
-    var text = commandInput.current!.value + "\n";
-    var op = {range: selection, text: text, forceMoveMarkers: false};
-    editor.executeEdits("my-source", [op], editor.getSelections());
+    editor.executeEdits("command-line", [{
+      range: monaco.Selection.fromPositions(
+        editor.getPosition(),
+        editor.getModel().getFullModelRange().getEndPosition()
+      ),
+      text: commandInput.current!.value + "\n",
+      forceMoveMarkers: false
+    }]);
     setProcessing(true)
   }
 
   useServerNotificationEffect('textDocument/publishDiagnostics', (params: PublishDiagnosticsParams) => {
     if (params.uri == editor.getModel().uri.toString()) {
       setProcessing(false)
-      const hasErrorsOrWarnings = params.diagnostics.some(
-        (d) =>
-          !d.message.startsWith("unsolved goals") &&
-          (d.severity == DiagnosticSeverity.Error || d.severity == DiagnosticSeverity.Warning)
-      )
-      if (!hasErrorsOrWarnings) {
+      if (!hasErrorsOrWarnings(params.diagnostics)) {
         commandInput.current!.value = "";
         editor.setPosition(editor.getModel().getFullModelRange().getEndPosition())
       }
@@ -50,7 +74,7 @@ export function CommandLine() {
   return <div className="command-line">
       <form onSubmit={handleSubmit}>
         <input type="text" ref={commandInput} disabled={processing} />
-        <button type="submit" disabled={processing} className="btn"><FontAwesomeIcon icon={faWandMagicSparkles} /> Run</button>
+        <button type="submit" disabled={processing} className="btn btn-inverted"><FontAwesomeIcon icon={faWandMagicSparkles} /> Run</button>
       </form>
     </div>
 }
diff --git a/client/src/components/infoview/info.tsx b/client/src/components/infoview/info.tsx
index f4715d2..dfe66a9 100644
--- a/client/src/components/infoview/info.tsx
+++ b/client/src/components/infoview/info.tsx
@@ -112,7 +112,6 @@ const InfoDisplayContent = React.memo((props: InfoDisplayContentProps) => {
     }), [selectedLocs])
 
     const goalFilter = { reverse: false, showType: true, showInstance: true, showHiddenAssumption: true, showLetValue: true }
-
     /* Adding {' '} to manage string literals properly: https://reactjs.org/docs/jsx-in-depth.html#string-literals-1 */
     return <>
         {hasError &&
@@ -121,13 +120,13 @@ const InfoDisplayContent = React.memo((props: InfoDisplayContentProps) => {
                 <a className='link pointer dim' onClick={e => { e.preventDefault(); void triggerUpdate(); }}>{' '}Try again.</a>
             </div>}
         <LocationsContext.Provider value={locs}>
-            {goals && goals.goals.length > 0 && <div className="goals-section">
-                    <div className="goals-section-title">Main Goal</div>
-                    <Goal filter={goalFilter} key='mainGoal' goal={goals.goals[0]} showHints={true} />
-                </div>}
+            <div className="goals-section">
+                { goals && goals.goals.length > 0
+                  ? <><div className="goals-section-title">Main Goal</div>
+                    <Goal filter={goalFilter} key='mainGoal' goal={goals.goals[0]} showHints={true} /></>
+                  : <div className="goals-section-title">No Goals</div> }
+            </div>
         </LocationsContext.Provider>
-        {/* <FilteredGoals headerChildren='Expected type' key='term-goal'
-            goals={termGoal !== undefined ? {goals: [{...termGoal, hints: []}]} : undefined} /> */}
         {userWidgets.map(widget =>
             <details key={`widget::${widget.id}::${widget.range?.toString()}`} open>
                 <summary className='mv2 pointer'>{widget.name}</summary>
@@ -135,14 +134,6 @@ const InfoDisplayContent = React.memo((props: InfoDisplayContentProps) => {
                     selectedLocations={selectedLocs} widget={widget}/>
             </details>
         )}
-        {/* <div style={{display: hasMessages ? 'block' : 'none'}} key='messages'>
-            <details key='messages' open>
-                <summary className='mv2 pointer'>Messages ({messages.length})</summary>
-                <div className='ml1'>
-                    <MessagesList uri={pos.uri} messages={messages} />
-                </div>
-            </details>
-        </div> */}
         {nothingToShow && (
             isPaused ?
                 /* Adding {' '} to manage string literals properly: https://reactjs.org/docs/jsx-in-depth.html#string-literals-1 */
diff --git a/client/src/components/level.css b/client/src/components/level.css
index bc98c13..542c587 100644
--- a/client/src/components/level.css
+++ b/client/src/components/level.css
@@ -24,7 +24,7 @@
   background-image: url('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAeCAYAAADkftS9AAAAIklEQVQoU2M4c+bMfxAGAgYYmwGrIIiDjrELjpo5aiZeMwF+yNnOs5KSvgAAAABJRU5ErkJggg==');
 }
 
-.main-panel, .info-panel {
+.main-panel, .info-panel, .doc-panel {
   height: 100%;
   overflow: auto;
 }
@@ -66,6 +66,9 @@
 .input-mode-switch {
   margin: .5em 0;
   float: right;
+  display: flex;
+  flex-direction: row;
+  gap: 1em;
 }
 
 .doc-panel li {