Taking a snapshot while I update packages in batches.... At least things are working again.

src/lib/elements/codemirror_modules.ts

@@ -1,7 +1,6 @@
 let _cmCache: {
     EditorView?: any;
     EditorState?: any;
-    basicSetup?: any;
     markdown?: any;
     markdownLanguage?: any;
     keymap?: any;
@@ -44,7 +43,6 @@ import { browser } from '$app/environment';
 type CMCache = {
     EditorView: any;
     EditorState: any;
-    basicSetup?: any;
     markdown?: any;
     markdownLanguage?: any;
     keymap?: any;
@@ -93,7 +91,6 @@ export async function ensureCodeMirrorModules(): Promise<CMCache> {
     const [
         viewMod,
         stateMod,
-        basicSetupMod,
         markdownMod,
         commandsMod,
         languageMod,
@@ -104,7 +101,6 @@ export async function ensureCodeMirrorModules(): Promise<CMCache> {
     ] = await Promise.all([
         import('@codemirror/view'),
         import('@codemirror/state'),
-        import('@codemirror/basic-setup'),
         import('@codemirror/lang-markdown'),
         import('@codemirror/commands'),
         import('@codemirror/language'),
@@ -135,8 +131,6 @@ export async function ensureCodeMirrorModules(): Promise<CMCache> {
         EditorState_allowMultipleSelections: stateMod.EditorState.allowMultipleSelections,
         EditorState_readOnly: stateMod.EditorState.readOnly,
 
-        basicSetup: basicSetupMod?.basicSetup,
-
         markdown: markdownMod?.markdown,
         markdownLanguage: markdownMod?.markdownLanguage,
         languages: languageMod?.languages, // From @codemirror/language-data, often re-exported by @codemirror/language