diff --git a/.eslintrc.js b/.eslintrc.js
index 542b96c06..d74a4b582 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -18,7 +18,6 @@ module.exports = {
     'max-len': ['error', 180],
     'no-trailing-spaces': 'error',
     'prefer-const': 0,
-    '@typescript-eslint/explicit-function-return-type': 0,
-    '@typescript-eslint/ban-ts-comment': 0
+    '@typescript-eslint/ban-ts-comment': 0,
   }
 };
diff --git a/src/dd-draggable.ts b/src/dd-draggable.ts
index 1b895d350..a207c535c 100644
--- a/src/dd-draggable.ts
+++ b/src/dd-draggable.ts
@@ -155,10 +155,10 @@ export class DDDraggable extends DDBaseImplement implements HTMLElementExtendOpt
       this.dragEl.addEventListener('touchmove', touchmove);
       this.dragEl.addEventListener('touchend', touchend);
     }
-    
+
     e.preventDefault();
     // preventDefault() prevents blur event which occurs just after mousedown event.
-    // if an editable content has focus, then blur must be call 
+    // if an editable content has focus, then blur must be call
     if(document.activeElement) (document.activeElement  as HTMLElement).blur();
 
     DDManager.mouseHandled = true;
@@ -166,7 +166,7 @@ export class DDDraggable extends DDBaseImplement implements HTMLElementExtendOpt
   }
 
   /** @internal method to call actual drag event */
-  protected _callDrag(e: DragEvent) {
+  protected _callDrag(e: DragEvent): void {
     if (!this.dragging) return;
     const ev = Utils.initEvent<DragEvent>(e, { target: this.el, type: 'drag' });
     if (this.option.drag) {
diff --git a/src/dd-droppable.ts b/src/dd-droppable.ts
index 2d9b08773..a439a40ea 100644
--- a/src/dd-droppable.ts
+++ b/src/dd-droppable.ts
@@ -9,12 +9,13 @@ import { DDBaseImplement, HTMLElementExtendOpt } from './dd-base-impl';
 import { Utils } from './utils';
 import { DDElementHost } from './dd-element';
 import { isTouch, pointerenter, pointerleave } from './dd-touch';
+import { DDUIData } from './types';
 
 export interface DDDroppableOpt {
   accept?: string | ((el: HTMLElement) => boolean);
-  drop?: (event: DragEvent, ui) => void;
-  over?: (event: DragEvent, ui) => void;
-  out?: (event: DragEvent, ui) => void;
+  drop?: (event: DragEvent, ui: DDUIData) => void;
+  over?: (event: DragEvent, ui: DDUIData) => void;
+  out?: (event: DragEvent, ui: DDUIData) => void;
 }
 
 // let count = 0; // TEST
@@ -163,7 +164,7 @@ export class DDDroppable extends DDBaseImplement implements HTMLElementExtendOpt
   }
 
   /** @internal */
-  protected _ui(drag: DDDraggable) {
+  protected _ui(drag: DDDraggable): DDUIData {
     return {
       draggable: drag.el,
       ...drag.ui()
diff --git a/src/dd-resizable-handle.ts b/src/dd-resizable-handle.ts
index 88aba5b4f..f142b892a 100644
--- a/src/dd-resizable-handle.ts
+++ b/src/dd-resizable-handle.ts
@@ -72,7 +72,7 @@ export class DDResizableHandle {
   }
 
   /** @internal called on mouse down on us: capture move on the entire document (mouse might not stay on us) until we release the mouse */
-  protected _mouseDown(e: MouseEvent) {
+  protected _mouseDown(e: MouseEvent): void {
     this.mouseDownEvent = e;
     document.addEventListener('mousemove', this._mouseMove, true); // capture, not bubble
     document.addEventListener('mouseup', this._mouseUp, true);
@@ -85,7 +85,7 @@ export class DDResizableHandle {
   }
 
   /** @internal */
-  protected _mouseMove(e: MouseEvent) {
+  protected _mouseMove(e: MouseEvent): void {
     let s = this.mouseDownEvent;
     if (this.moving) {
       this._triggerEvent('move', e);
@@ -100,7 +100,7 @@ export class DDResizableHandle {
   }
 
   /** @internal */
-  protected _mouseUp(e: MouseEvent) {
+  protected _mouseUp(e: MouseEvent): void {
     if (this.moving) {
       this._triggerEvent('stop', e);
     }
diff --git a/src/dd-resizable.ts b/src/dd-resizable.ts
index edb7bfcaf..9c9a92066 100644
--- a/src/dd-resizable.ts
+++ b/src/dd-resizable.ts
@@ -126,7 +126,8 @@ export class DDResizable extends DDBaseImplement implements HTMLElementExtendOpt
   }
 
   /** @internal */
-  protected _mouseOver(e: Event) {
+  // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  protected _mouseOver(e: Event): void {
     // console.log(`${count++} pre-enter ${(this.el as GridItemHTMLElement).gridstackNode._id}`)
     // already over a child, ignore. Ideally we just call e.stopPropagation() but see https://github.com/gridstack/gridstack.js/issues/2018
     if (DDManager.overResizeElement || DDManager.dragElement) return;
@@ -136,7 +137,8 @@ export class DDResizable extends DDBaseImplement implements HTMLElementExtendOpt
   }
 
   /** @internal */
-  protected _mouseOut(e: Event) {
+  // eslint-disable-next-line @typescript-eslint/no-unused-vars
+  protected _mouseOut(e: Event): void {
     // console.log(`${count++} pre-leave ${(this.el as GridItemHTMLElement).gridstackNode._id}`)
     if (DDManager.overResizeElement !== this) return;
     delete DDManager.overResizeElement;
diff --git a/src/dd-touch.ts b/src/dd-touch.ts
index 544406b31..62a3bc382 100644
--- a/src/dd-touch.ts
+++ b/src/dd-touch.ts
@@ -14,8 +14,10 @@ export const isTouch: boolean = typeof window !== 'undefined' && typeof document
 ( 'ontouchstart' in document
   || 'ontouchstart' in window
   // || !!window.TouchEvent // true on Windows 10 Chrome desktop so don't use this
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
   || ((window as any).DocumentTouch && document instanceof (window as any).DocumentTouch)
   || navigator.maxTouchPoints > 0
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
   || (navigator as any).msMaxTouchPoints > 0
 );
 
@@ -114,7 +116,7 @@ function simulatePointerMouseEvent(e: PointerEvent, simulatedType: string) {
  * Handle the touchstart events
  * @param {Object} e The widget element's touchstart event
  */
-export function touchstart(e: TouchEvent) {
+export function touchstart(e: TouchEvent): void {
   // Ignore the event if another widget is already being handled
   if (DDTouch.touchHandled) return;  DDTouch.touchHandled = true;
 
@@ -128,7 +130,7 @@ export function touchstart(e: TouchEvent) {
  * Handle the touchmove events
  * @param {Object} e The document's touchmove event
  */
-export function touchmove(e: TouchEvent) {
+export function touchmove(e: TouchEvent): void {
   // Ignore event if not handled by us
   if (!DDTouch.touchHandled)  return;
 
@@ -139,7 +141,7 @@ export function touchmove(e: TouchEvent) {
  * Handle the touchend events
  * @param {Object} e The document's touchend event
  */
-export function touchend(e: TouchEvent) {
+export function touchend(e: TouchEvent): void {
 
   // Ignore event if not handled
   if (!DDTouch.touchHandled) return;
@@ -170,11 +172,11 @@ export function touchend(e: TouchEvent) {
  * see https://stackoverflow.com/questions/27908339/js-touch-equivalent-for-mouseenter
  * so instead of PointerEvent to still get enter/leave and send the matching mouse event.
  */
-export function pointerdown(e: PointerEvent) {
+export function pointerdown(e: PointerEvent): void {
   (e.target as HTMLElement).releasePointerCapture(e.pointerId) // <- Important!
 }
 
-export function pointerenter(e: PointerEvent) {
+export function pointerenter(e: PointerEvent): void {
   // ignore the initial one we get on pointerdown on ourself
   if (!DDManager.dragElement) {
     // console.log('pointerenter ignored');
@@ -184,7 +186,7 @@ export function pointerenter(e: PointerEvent) {
   simulatePointerMouseEvent(e, 'mouseenter');
 }
 
-export function pointerleave(e: PointerEvent) {
+export function pointerleave(e: PointerEvent): void {
   // ignore the leave on ourself we get before releasing the mouse over ourself
   // by delaying sending the event and having the up event cancel us
   if (!DDManager.dragElement) {
diff --git a/src/gridstack-engine.ts b/src/gridstack-engine.ts
index 4c9d17240..5844e702a 100644
--- a/src/gridstack-engine.ts
+++ b/src/gridstack-engine.ts
@@ -4,7 +4,7 @@
  */
 
 import { Utils } from './utils';
-import { GridStackNode, ColumnOptions, GridStackPosition, GridStackMoveOpts, GridStackOptions } from './types';
+import { GridStackNode, ColumnOptions, GridStackPosition, GridStackMoveOpts } from './types';
 
 /** callback to update the DOM attributes since this class is generic (no HTML or other info) for items that changed - see _notify() */
 type OnChangeCB = (nodes: GridStackNode[]) => void;
diff --git a/src/gridstack.ts b/src/gridstack.ts
index eeca20ca9..9961fce49 100644
--- a/src/gridstack.ts
+++ b/src/gridstack.ts
@@ -41,6 +41,11 @@ interface GridCSSStyleSheet extends CSSStyleSheet {
   _max?: number; // internal tracker of the max # of rows we created
 }
 
+// extend with internal fields we need - TODO: move other items in here
+interface InternalGridStackOptions extends GridStackOptions {
+  _alwaysShowResizeHandle?: true | false | 'mobile'; // so we can restore for save
+}
+
 /**
  * Main gridstack class - you will need to call `GridStack.init()` first to initialize your grid.
  * Note: your grid elements MUST have the following classes for the CSS layout to work:
@@ -141,7 +146,7 @@ export class GridStack {
    * See instead `GridStackOptions.engineClass` if you only need to
    * replace just one instance.
    */
-  static registerEngine(engineClass: typeof GridStackEngine) {
+  static registerEngine(engineClass: typeof GridStackEngine): void {
     GridStack.engineClass = engineClass;
   }
 
@@ -237,7 +242,7 @@ export class GridStack {
     }
     // save original setting so we can restore on save
     if (opts.alwaysShowResizeHandle !== undefined) {
-      (opts as any)._alwaysShowResizeHandle = opts.alwaysShowResizeHandle;
+      (opts as InternalGridStackOptions)._alwaysShowResizeHandle = opts.alwaysShowResizeHandle;
     }
 
     // elements DOM attributes override any passed options (like CSS style) - merge the two together
@@ -575,7 +580,7 @@ export class GridStack {
 
     // check if save entire grid options (needed for recursive) + children...
     if (saveGridOpt) {
-      let o: GridStackOptions = Utils.cloneDeep(this.opts);
+      let o: InternalGridStackOptions = Utils.cloneDeep(this.opts);
       // delete default values that will be recreated on launch
       if (o.marginBottom === o.marginTop && o.marginRight === o.marginLeft && o.marginTop === o.marginRight) {
         o.margin = o.marginTop;
@@ -589,8 +594,8 @@ export class GridStack {
         o.column = 'auto';
         delete o.disableOneColumnMode;
       }
-      const origShow = (o as any)._alwaysShowResizeHandle;
-      delete (o as any)._alwaysShowResizeHandle;
+      const origShow = o._alwaysShowResizeHandle;
+      delete o._alwaysShowResizeHandle;
       if (origShow !== undefined) {
         o.alwaysShowResizeHandle = origShow;
       } else {
diff --git a/src/types.ts b/src/types.ts
index 0fb24b6f3..3dd630154 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -361,6 +361,7 @@ export interface Rect extends Size, Position {}
 export interface DDUIData {
   position?: Position;
   size?: Size;
+  draggable?: HTMLElement;
   /* fields not used by GridStack but sent by jq ? leave in case we go back to them...
   originalPosition? : Position;
   offset?: Position;
diff --git a/src/utils.ts b/src/utils.ts
index 3c4c7d207..b644fdeb0 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -273,7 +273,7 @@ export class Utils {
   }
 
   /** removes internal fields '_' and default values for saving */
-  static removeInternalForSave(n: GridStackNode, removeEl = true) {
+  static removeInternalForSave(n: GridStackNode, removeEl = true): void {
     for (let key in n) { if (key[0] === '_' || n[key] === null || n[key] === undefined ) delete n[key]; }
     delete n.grid;
     if (removeEl) delete n.el;
@@ -496,7 +496,7 @@ export class Utils {
   }
 
   /** copies the MouseEvent properties and sends it as another event to the given target */
-  public static simulateMouseEvent(e: MouseEvent, simulatedType: string, target?: EventTarget) {
+  public static simulateMouseEvent(e: MouseEvent, simulatedType: string, target?: EventTarget): void {
     const simulatedEvent = document.createEvent('MouseEvents');
     simulatedEvent.initMouseEvent(
       simulatedType, // type