diff --git a/src/vs/vscode.d.ts b/src/vs/vscode.d.ts
index 1bd37d77e13..ae956d9842b 100644
--- a/src/vs/vscode.d.ts
+++ b/src/vs/vscode.d.ts
@@ -3249,6 +3249,13 @@ declare module 'vscode' {
 		 */
 		commitCharacters?: string[];
 
+		/**
+		 * Keep whitespace of the [insertText](#CompletionItem.insertText) as is. By default, the editor adjusts leading
+		 * whitespace of new lines so that they match the indentation of the line for which the item is accepeted - setting
+		 * this to `true` will prevent that.
+		 */
+		keepWhitespace?: boolean;
+
 		/**
 		 * @deprecated Use `CompletionItem.insertText` and `CompletionItem.range` instead.
 		 *
diff --git a/src/vs/vscode.proposed.d.ts b/src/vs/vscode.proposed.d.ts
index 31bbbe43cb1..589a0326445 100644
--- a/src/vs/vscode.proposed.d.ts
+++ b/src/vs/vscode.proposed.d.ts
@@ -20,33 +20,6 @@ declare module 'vscode' {
 		export function sampleFunction(): Thenable<any>;
 	}
 
-	//#region Joh - https://github.com/Microsoft/vscode/issues/57093
-
-	/**
-	 * An insert text rule defines how the [`insertText`](#CompletionItem.insertText) of a
-	 * completion item should be modified.
-	 */
-	export enum CompletionItemInsertTextRule {
-
-		/**
-		 * Keep whitespace as is. By default, the editor adjusts leading
-		 * whitespace of new lines so that they match the indentation of
-		 * the line for which the item is accepeted.
-		 */
-		KeepWhitespace = 0b01
-	}
-
-	export interface CompletionItem {
-
-		/**
-		 * Rules about how/if the `insertText` should be modified by the
-		 * editor. Can be a bit mask of many rules.
-		 */
-		insertTextRules?: CompletionItemInsertTextRule;
-	}
-
-	//#endregion
-
 	//#region Joh - read/write in chunks
 
 	export interface FileSystemProvider {
diff --git a/src/vs/workbench/api/node/extHost.api.impl.ts b/src/vs/workbench/api/node/extHost.api.impl.ts
index 834d2df052a..8121df2ac83 100644
--- a/src/vs/workbench/api/node/extHost.api.impl.ts
+++ b/src/vs/workbench/api/node/extHost.api.impl.ts
@@ -744,7 +744,6 @@ export function createApiFactory(
 			CommentThreadCollapsibleState: extHostTypes.CommentThreadCollapsibleState,
 			CompletionItem: extHostTypes.CompletionItem,
 			CompletionItemKind: extHostTypes.CompletionItemKind,
-			CompletionItemInsertTextRule: extension.enableProposedApi ? extHostTypes.CompletionItemInsertTextRule : null,
 			CompletionList: extHostTypes.CompletionList,
 			CompletionTriggerKind: extHostTypes.CompletionTriggerKind,
 			ConfigurationTarget: extHostTypes.ConfigurationTarget,
diff --git a/src/vs/workbench/api/node/extHostLanguageFeatures.ts b/src/vs/workbench/api/node/extHostLanguageFeatures.ts
index e9696659033..6e12e68ca9b 100644
--- a/src/vs/workbench/api/node/extHostLanguageFeatures.ts
+++ b/src/vs/workbench/api/node/extHostLanguageFeatures.ts
@@ -685,7 +685,7 @@ class SuggestAdapter {
 			//
 			range: undefined,
 			insertText: undefined,
-			insertTextRules: typeConvert.CompletionItemInsertTextRule.from(item.insertTextRules),
+			insertTextRules: item.keepWhitespace ? modes.CompletionItemInsertTextRule.KeepWhitespace : 0,
 			additionalTextEdits: item.additionalTextEdits && item.additionalTextEdits.map(typeConvert.TextEdit.from),
 			command: this._commands.toInternal(item.command),
 			commitCharacters: item.commitCharacters,
diff --git a/src/vs/workbench/api/node/extHostTypeConverters.ts b/src/vs/workbench/api/node/extHostTypeConverters.ts
index 0bbe5c7e66b..e50f4755d58 100644
--- a/src/vs/workbench/api/node/extHostTypeConverters.ts
+++ b/src/vs/workbench/api/node/extHostTypeConverters.ts
@@ -681,25 +681,6 @@ export namespace CompletionItemKind {
 	}
 }
 
-export namespace CompletionItemInsertTextRule {
-
-	export function from(rule: types.CompletionItemInsertTextRule): modes.CompletionItemInsertTextRule {
-		let result = 0;
-		if ((rule & types.CompletionItemInsertTextRule.KeepWhitespace)) {
-			result += modes.CompletionItemInsertTextRule.KeepWhitespace;
-		}
-		return result;
-	}
-
-	export function to(rule: modes.CompletionItemInsertTextRule): types.CompletionItemInsertTextRule {
-		let result = 0;
-		if ((rule & modes.CompletionItemInsertTextRule.KeepWhitespace)) {
-			result += types.CompletionItemInsertTextRule.KeepWhitespace;
-		}
-		return result;
-	}
-}
-
 export namespace CompletionItem {
 
 	export function to(suggestion: modes.CompletionItem): types.CompletionItem {
@@ -713,7 +694,7 @@ export namespace CompletionItem {
 		result.preselect = suggestion.preselect;
 		result.commitCharacters = suggestion.commitCharacters;
 		result.range = Range.to(suggestion.range);
-		result.insertTextRules = CompletionItemInsertTextRule.to(suggestion.insertTextRules);
+		result.keepWhitespace = Boolean(suggestion.insertTextRules & modes.CompletionItemInsertTextRule.KeepWhitespace);
 		// 'inserText'-logic
 		if (suggestion.insertTextRules & modes.CompletionItemInsertTextRule.InsertAsSnippet) {
 			result.insertText = new types.SnippetString(suggestion.insertText);
diff --git a/src/vs/workbench/api/node/extHostTypes.ts b/src/vs/workbench/api/node/extHostTypes.ts
index f4d5445d036..62a81f6a104 100644
--- a/src/vs/workbench/api/node/extHostTypes.ts
+++ b/src/vs/workbench/api/node/extHostTypes.ts
@@ -1163,10 +1163,6 @@ export enum CompletionItemKind {
 	TypeParameter = 24
 }
 
-export enum CompletionItemInsertTextRule {
-	KeepWhitespace = 0b1
-}
-
 export class CompletionItem implements vscode.CompletionItem {
 
 	label: string;
@@ -1177,7 +1173,7 @@ export class CompletionItem implements vscode.CompletionItem {
 	filterText: string;
 	preselect: boolean;
 	insertText: string | SnippetString;
-	insertTextRules: CompletionItemInsertTextRule;
+	keepWhitespace?: boolean;
 	range: Range;
 	commitCharacters: string[];
 	textEdit: TextEdit;