Add an application for controlling the size settings.

module/apps/ResizeControlManager.mjs

@@ -0,0 +1,67 @@
+import { __ID__, filePath } from "../consts.mjs";
+
+const { HandlebarsApplicationMixin, DocumentSheetV2 } = foundry.applications.api;
+const { getProperty } = foundry.utils;
+
+export class ResizeControlManager extends HandlebarsApplicationMixin(DocumentSheetV2) {
+
+	// #region Options
+	static DEFAULT_OPTIONS = {
+		classes: [
+			__ID__,
+			`ResizeControlManager`,
+		],
+		position: {
+			width: 400,
+			height: `auto`,
+		},
+		window: {
+			resizable: true,
+		},
+		form: {
+			submitOnChange: false,
+			closeOnSubmit: true,
+		},
+		actions: {},
+	};
+
+	static PARTS = {
+		settings: { template: filePath(`templates/ResizeControlManager/settings.hbs`) },
+		controls: { template: filePath(`templates/ResizeControlManager/controls.hbs`) },
+	};
+	// #endregion Options
+
+	// #region Instance Data
+	get title() {
+		return `Sizing Settings For : ${this.document.name}`;
+	};
+	// #endregion Instance Data
+
+	// #region Lifecycle
+	async _onRender(context, options) {
+		await super._onRender(context, options);
+	};
+	// #endregion Lifecycle
+
+	// #region Data Prep
+	async _prepareContext() {
+		const sizing = getProperty(this.document, `flags.${__ID__}.PlayerSheet.size`) ?? {};
+
+		const ctx = {
+			meta: {
+				idp: this.id,
+			},
+			width: sizing.width,
+			height: sizing.height,
+			resizable: sizing.resizable,
+			resizeOptions: [
+				{ label: `Default`, value: `` },
+				{ label: `Resizable`, value: `true` },
+				{ label: `No Resizing`, value: `false` },
+			],
+		};
+
+		return ctx;
+	};
+	// #endregion Data Prep
+};