diff --git a/src/SaveObject.tsx b/src/SaveObject.tsx
index bd4e766d6..daa4a5b0e 100755
--- a/src/SaveObject.tsx
+++ b/src/SaveObject.tsx
@@ -480,12 +480,6 @@ function evaluateVersionCompatibility(ver: string | number): void {
   if (ver < 23) {
     anyPlayer.currentWork = null;
   }
-  if (ver < 24) {
-    // Assert the relevant type that was in effect at this version.
-    (Player.getHomeComputer().scripts as unknown as { filename: string }[]).forEach(
-      (s) => s.filename.endsWith(".ns") && (s.filename += ".js"),
-    );
-  }
   if (ver < 25) {
     const removePlayerFields = [
       "hacking_chance_mult",
diff --git a/src/ScriptEditor/ui/themes.ts b/src/ScriptEditor/ui/themes.ts
index b9cee6d8a..b8751c6d6 100644
--- a/src/ScriptEditor/ui/themes.ts
+++ b/src/ScriptEditor/ui/themes.ts
@@ -1,4 +1,6 @@
 import type { editor } from "monaco-editor";
+import { getRecordKeys } from "../../Types/Record";
+import { Settings } from "../../Settings/Settings";
 type DefineThemeFn = typeof editor.defineTheme;
 
 export interface IScriptEditorTheme {
@@ -72,8 +74,13 @@ const colorRegExp = /^#?([0-9A-Fa-f]{6})([0-9A-Fa-f]{2})?$/;
 // Recursively sanitize the theme data to prevent errors
 // Invalid data will be replaced with FF0000 (bright red)
 export const sanitizeTheme = (theme: IScriptEditorTheme): void => {
-  for (const [k, v] of Object.entries(theme)) {
-    switch (k) {
+  if (typeof theme !== "object") {
+    Settings.EditorTheme = defaultMonacoTheme;
+    return;
+  }
+  for (const themeKey of getRecordKeys(theme)) {
+    if (typeof theme[themeKey] !== "object") delete theme[themeKey];
+    switch (themeKey) {
       case "base":
         if (!["vs-dark", "vs"].includes(theme.base)) theme.base = "vs-dark";
         continue;
@@ -82,14 +89,17 @@ export const sanitizeTheme = (theme: IScriptEditorTheme): void => {
         continue;
     }
 
-    const repairBlock = (block: Record<string, object | string>): void => {
-      for (const [k, v] of Object.entries(block)) {
-        if (typeof v === "object") {
-          repairBlock(v as Record<string, string>);
-        } else if (!v.match(colorRegExp)) block[k] = "FF0000";
+    const block = theme[themeKey];
+    function repairBlock<T extends Record<string, unknown>>(block: T) {
+      for (const [blockKey, blockValue] of Object.entries(block) as [keyof T, unknown][]) {
+        if (!blockValue || (typeof blockValue !== "string" && typeof blockValue !== "object"))
+          (block[blockKey] as string) = "FF0000";
+        else if (typeof blockValue === "object") repairBlock(block);
+        else if (!blockValue.match(colorRegExp)) (block[blockKey] as string) = "FF0000";
       }
-    };
-    repairBlock(v);
+    }
+    // Type assertion is to something less specific.
+    repairBlock(block);
   }
 };
 
diff --git a/src/Server/BaseServer.ts b/src/Server/BaseServer.ts
index d2d132d0e..b41e7c048 100644
--- a/src/Server/BaseServer.ts
+++ b/src/Server/BaseServer.ts
@@ -333,6 +333,8 @@ export abstract class BaseServer implements IServer {
     server.scripts = new JSONMap();
     // In case somehow there are previously valid filenames that can't be sanitized, they will go in a new directory with a note.
     for (const script of oldScripts) {
+      // We're about to do type validation on the filename anyway.
+      if (script.filename.endsWith(".ns")) script.filename = (script.filename + ".js") as any;
       let newFilePath = resolveScriptFilePath(script.filename);
       if (!newFilePath) {
         newFilePath = `${newDirectory}script${++invalidScriptCount}.js` as ScriptFilePath;