diff --git a/src/App.ts b/src/App.ts
index 391642dd5..5a5e35242 100644
--- a/src/App.ts
+++ b/src/App.ts
@@ -82,7 +82,16 @@ export async function setup() {
 
 	if (fileSystem instanceof TauriFileSystem) await setupTauriFileSystem()
 
-	if (fileSystem instanceof LocalFileSystem) fileSystem.setRootName('fileSystemPolyfill')
+	if (fileSystem instanceof LocalFileSystem) {
+		fileSystem.setRootName('fileSystemPolyfill')
+
+		// On browsers without the File System Access API (e.g. Safari, Firefox, Android Chrome) the
+		// entire project lives in IndexedDB. Request persistent storage so the browser doesn't evict
+		// it, which otherwise causes saved files to silently disappear.
+		if (navigator.storage?.persist) {
+			navigator.storage.persist().catch(() => {})
+		}
+	}
 
 	setupTypescript()
 	setupLang()
diff --git a/src/components/Windows/Presets/Presets.vue b/src/components/Windows/Presets/Presets.vue
index a7b380826..773fde00d 100644
--- a/src/components/Windows/Presets/Presets.vue
+++ b/src/components/Windows/Presets/Presets.vue
@@ -76,6 +76,32 @@ const validationError: ComputedRef<string | null> = computed(() => {
 	return null
 })
 
+function openFileInput(fieldId: string) {
+	const input = document.getElementById(`preset-file-input-${fieldId}`)
+
+	if (input instanceof HTMLInputElement) input.click()
+}
+
+async function onFileInputChange(event: Event, fieldId: string) {
+	const input = <HTMLInputElement>event.target
+
+	const file = input.files?.[0]
+
+	if (!file) return
+
+	const content = new Uint8Array(await file.arrayBuffer())
+
+	// Store a fake file handle matching the shape that preset scripts (and loadPresetFile) expect:
+	// `name` + `content` (binary, read by createFile) + `text()` (read by e.g. the Block Model script).
+	createPresetOptions.value[fieldId] = {
+		name: file.name,
+		content,
+		async text() {
+			return new TextDecoder().decode(content)
+		},
+	}
+}
+
 async function create() {
 	if (validationError.value !== null) return
 
@@ -214,15 +240,22 @@ watch(filteredCategories, () => {
 								class="mb-6 flex bg-background"
 								v-slot="{ focus, blur }"
 							>
-								<input type="file" class="hidden" />
+								<input
+									:id="`preset-file-input-${fieldId}`"
+									type="file"
+									class="hidden"
+									:accept="fieldOptions.accept"
+									@change="(event: Event) => onFileInputChange(event, fieldId)"
+								/>
 
 								<button
 									class="flex align-center gap-2 text-text-secondary font-theme placeholder:text-text-secondary"
 									@mouseenter="focus"
 									@mouseleave="blur"
+									@click="openFileInput(fieldId)"
 								>
 									<Icon icon="image" class="no-fill" color="text-text-secondary" />
-									{{ fieldName }}
+									{{ createPresetOptions[fieldId]?.name ?? fieldName }}
 								</button>
 							</LabeledInput>
 
diff --git a/src/libs/compiler/DashService.ts b/src/libs/compiler/DashService.ts
index 7113c5dc8..3916ea81c 100644
--- a/src/libs/compiler/DashService.ts
+++ b/src/libs/compiler/DashService.ts
@@ -71,7 +71,10 @@ export class DashService implements AsyncDisposable {
 		await sendAndWait(
 			{
 				action: 'setup',
-				config: this.project.config,
+				// Pass a plain, structured-clone-safe copy of the config. Safari's structured clone
+				// is stricter than Chromium's and throws DataCloneError on non-plain objects, which
+				// broke .mcaddon exports (the only export path that hands data to the Dash worker).
+				config: this.project.config ? JSON.parse(JSON.stringify(this.project.config)) : this.project.config,
 				mode,
 				configPath: join(this.project.path, 'config.json'),
 				compilerConfigPath,
diff --git a/src/libs/fileSystem/LocalFileSystem.ts b/src/libs/fileSystem/LocalFileSystem.ts
index 7972c7ce5..1cd8f5f0a 100644
--- a/src/libs/fileSystem/LocalFileSystem.ts
+++ b/src/libs/fileSystem/LocalFileSystem.ts
@@ -173,7 +173,14 @@ export class LocalFileSystem extends BaseFileSystem {
 
 		path = resolve('/', path)
 
-		await del(`localFileSystem/${this.rootName}${path}`)
+		// Remove the directory entry itself as well as every file and subdirectory nested inside of it.
+		// idb-keyval has no concept of folders, so deleting only the directory key would orphan its children.
+		const directoryKey = `localFileSystem/${this.rootName}${path}`
+		const childPrefix = `${directoryKey}/`
+
+		const childKeys = (await keys()).filter((key) => key.toString().startsWith(childPrefix))
+
+		await Promise.all([del(directoryKey), ...childKeys.map((key) => del(key))])
 
 		if (
 			this.pathsToWatch.find((watchPath) => path.startsWith(watchPath)) !== undefined &&