diff --git a/webview-ui/src/components/modes/ModesView.tsx b/webview-ui/src/components/modes/ModesView.tsx
index 170d03b0e4..16cef65e1f 100644
--- a/webview-ui/src/components/modes/ModesView.tsx
+++ b/webview-ui/src/components/modes/ModesView.tsx
@@ -833,7 +833,7 @@ const ModesView = ({ onDone }: ModesViewProps) => {
 							})()}
 							onChange={(e) => {
 								const value =
-									(e as unknown as CustomEvent)?.detail?.target?.value ||
+									(e as unknown as CustomEvent)?.detail?.target?.value ??
 									((e as any).target as HTMLTextAreaElement).value
 								const customMode = findModeBySlug(visualMode, customModes)
 								if (customMode) {
@@ -888,7 +888,7 @@ const ModesView = ({ onDone }: ModesViewProps) => {
 							})()}
 							onChange={(e) => {
 								const value =
-									(e as unknown as CustomEvent)?.detail?.target?.value ||
+									(e as unknown as CustomEvent)?.detail?.target?.value ??
 									((e as any).target as HTMLTextAreaElement).value
 								const customMode = findModeBySlug(visualMode, customModes)
 								if (customMode) {
@@ -943,7 +943,7 @@ const ModesView = ({ onDone }: ModesViewProps) => {
 							})()}
 							onChange={(e) => {
 								const value =
-									(e as unknown as CustomEvent)?.detail?.target?.value ||
+									(e as unknown as CustomEvent)?.detail?.target?.value ??
 									((e as any).target as HTMLTextAreaElement).value
 								const customMode = findModeBySlug(visualMode, customModes)
 								if (customMode) {
@@ -1102,7 +1102,7 @@ const ModesView = ({ onDone }: ModesViewProps) => {
 							})()}
 							onChange={(e) => {
 								const value =
-									(e as unknown as CustomEvent)?.detail?.target?.value ||
+									(e as unknown as CustomEvent)?.detail?.target?.value ??
 									((e as any).target as HTMLTextAreaElement).value
 								const customMode = findModeBySlug(visualMode, customModes)
 								if (customMode) {
@@ -1307,7 +1307,7 @@ const ModesView = ({ onDone }: ModesViewProps) => {
 						value={customInstructions || ""}
 						onChange={(e) => {
 							const value =
-								(e as unknown as CustomEvent)?.detail?.target?.value ||
+								(e as unknown as CustomEvent)?.detail?.target?.value ??
 								((e as any).target as HTMLTextAreaElement).value
 							setCustomInstructions(value || undefined)
 							vscode.postMessage({
diff --git a/webview-ui/src/components/settings/PromptsSettings.tsx b/webview-ui/src/components/settings/PromptsSettings.tsx
index a71132d62b..c4b9e632d5 100644
--- a/webview-ui/src/components/settings/PromptsSettings.tsx
+++ b/webview-ui/src/components/settings/PromptsSettings.tsx
@@ -56,14 +56,21 @@ const PromptsSettings = ({ customSupportPrompts, setCustomSupportPrompts }: Prom
 	}, [])
 
 	const updateSupportPrompt = (type: SupportPromptType, value: string | undefined) => {
+		// Trim the value when storing, but keep empty strings
+		const trimmedValue = value?.trim()
+		const finalValue = trimmedValue === "" ? undefined : trimmedValue
+
 		if (type === "CONDENSE") {
-			setCustomCondensingPrompt(value || supportPrompt.default.CONDENSE)
+			setCustomCondensingPrompt(finalValue || supportPrompt.default.CONDENSE)
 			vscode.postMessage({
 				type: "updateCondensingPrompt",
-				text: value || supportPrompt.default.CONDENSE,
+				text: finalValue || supportPrompt.default.CONDENSE,
 			})
+			// Also update the customSupportPrompts to trigger change detection
+			const updatedPrompts = { ...customSupportPrompts, [type]: finalValue }
+			setCustomSupportPrompts(updatedPrompts)
 		} else {
-			const updatedPrompts = { ...customSupportPrompts, [type]: value }
+			const updatedPrompts = { ...customSupportPrompts, [type]: finalValue }
 			setCustomSupportPrompts(updatedPrompts)
 		}
 	}
@@ -75,6 +82,10 @@ const PromptsSettings = ({ customSupportPrompts, setCustomSupportPrompts }: Prom
 				type: "updateCondensingPrompt",
 				text: supportPrompt.default.CONDENSE,
 			})
+			// Also update the customSupportPrompts to trigger change detection
+			const updatedPrompts = { ...customSupportPrompts }
+			delete updatedPrompts[type]
+			setCustomSupportPrompts(updatedPrompts)
 		} else {
 			const updatedPrompts = { ...customSupportPrompts }
 			delete updatedPrompts[type]
@@ -147,10 +158,9 @@ const PromptsSettings = ({ customSupportPrompts, setCustomSupportPrompts }: Prom
 						value={getSupportPromptValue(activeSupportOption)}
 						onChange={(e) => {
 							const value =
-								(e as unknown as CustomEvent)?.detail?.target?.value ||
+								(e as unknown as CustomEvent)?.detail?.target?.value ??
 								((e as any).target as HTMLTextAreaElement).value
-							const trimmedValue = value.trim()
-							updateSupportPrompt(activeSupportOption, trimmedValue || undefined)
+							updateSupportPrompt(activeSupportOption, value)
 						}}
 						rows={6}
 						className="w-full"