diff --git a/spec/suites/core/EventsSpec.js b/spec/suites/core/EventsSpec.js
index 4a28bc2a4..59b56a0c3 100644
--- a/spec/suites/core/EventsSpec.js
+++ b/spec/suites/core/EventsSpec.js
@@ -634,9 +634,6 @@ describe('Events', () => {
 			expect(spy2.calledWith({
 				type: 'test2',
 				target: parent,
-				// layer should be deprecated in the future
-				// in favor of sourceTarget
-				layer: obj,
 				sourceTarget: obj,
 				propagatedFrom: obj
 			})).to.be.true;
diff --git a/spec/suites/dom/DomEvent.DoubleTapSpec.js b/spec/suites/dom/DomEvent.DoubleTapSpec.js
index 97218fa41..093a866cc 100644
--- a/spec/suites/dom/DomEvent.DoubleTapSpec.js
+++ b/spec/suites/dom/DomEvent.DoubleTapSpec.js
@@ -42,15 +42,6 @@ describe('DomEvent.DoubleTapSpec.js', () => {
 		expect(spy.notCalled).to.be.true;
 	});
 
-	it('does not fire dblclick when detail !== 1', () => {
-		UIEventSimulator.fire('click', container, {detail: 0}); // like in IE
-		clock.tick(100);
-		UIEventSimulator.fire('click', container, {detail: 0});
-		clock.tick(100);
-
-		expect(spy.notCalled).to.be.true;
-	});
-
 	it('does not fire dblclick after removeListener', () => {
 		DomEvent.off(container, 'dblclick', spy);
 
diff --git a/spec/suites/dom/DomEventSpec.js b/spec/suites/dom/DomEventSpec.js
index c993d1581..1c9845299 100644
--- a/spec/suites/dom/DomEventSpec.js
+++ b/spec/suites/dom/DomEventSpec.js
@@ -599,20 +599,13 @@ describe('DomEvent', () => {
 	});
 
 	describe('#preventDefault', () => {
-		function isPrevented(e) {
-			if ('defaultPrevented' in e) {
-				return e.defaultPrevented;
-			}
-			return !e.returnValue; // IE<11
-		}
-
 		it('prevents the default action of event', (done) => {
 			DomEvent.on(el, 'click', (e) => {
-				expect(isPrevented(e)).not.to.be.true; // control case
+				expect(e.defaultPrevented).not.to.be.true; // control case
 
 				DomEvent.preventDefault(e);
 
-				expect(isPrevented(e)).to.be.true;
+				expect(e.defaultPrevented).to.be.true;
 				done();
 			});
 
diff --git a/spec/suites/layer/GeoJSONSpec.js b/spec/suites/layer/GeoJSONSpec.js
index f5f35f068..8f912665f 100644
--- a/spec/suites/layer/GeoJSONSpec.js
+++ b/spec/suites/layer/GeoJSONSpec.js
@@ -154,7 +154,7 @@ describe('Marker#toGeoJSON', () => {
 
 describe('Circle#toGeoJSON', () => {
 	it('returns a 2D Point object', () => {
-		const circle = new Circle([10, 20], 100);
+		const circle = new Circle([10, 20], {radius: 100});
 		expect(circle.toGeoJSON().geometry).to.eql({
 			type: 'Point',
 			coordinates: [20, 10]
@@ -162,7 +162,7 @@ describe('Circle#toGeoJSON', () => {
 	});
 
 	it('returns a 3D Point object', () => {
-		const circle = new Circle([10, 20, 30], 100);
+		const circle = new Circle([10, 20, 30], {radius: 100});
 		expect(circle.toGeoJSON().geometry).to.eql({
 			type: 'Point',
 			coordinates: [20, 10, 30]
@@ -170,7 +170,7 @@ describe('Circle#toGeoJSON', () => {
 	});
 
 	it('should allow specific precisions', () => {
-		const circle = new Circle([10.1234, 20.1234, 30.1234], 100);
+		const circle = new Circle([10.1234, 20.1234, 30.1234], {radius: 100});
 		expect(circle.toGeoJSON(3).geometry).to.eql({
 			type: 'Point',
 			coordinates: [20.123, 10.123, 30.123]
diff --git a/spec/suites/layer/ImageOverlaySpec.js b/spec/suites/layer/ImageOverlaySpec.js
index af8da2af3..d550d4dbf 100644
--- a/spec/suites/layer/ImageOverlaySpec.js
+++ b/spec/suites/layer/ImageOverlaySpec.js
@@ -110,23 +110,23 @@ describe('ImageOverlay', () => {
 		it('should update the z-index of the image if it has allready been added to the map', () => {
 			const overlay = imageOverlay('', imageBounds);
 			overlay.addTo(map);
-			expect(overlay._image.style.zIndex).to.eql('1'); // Number type in IE
+			expect(overlay._image.style.zIndex).to.eql('1');
 
 			overlay.setZIndex('10');
-			expect(overlay._image.style.zIndex).to.eql('10'); // Number type in IE
+			expect(overlay._image.style.zIndex).to.eql('10');
 		});
 
 		it('should set the z-index of the image when it is added to the map', () => {
 			const overlay = imageOverlay('', imageBounds);
 			overlay.setZIndex('10');
 			overlay.addTo(map);
-			expect(overlay._image.style.zIndex).to.eql('10'); // Number type in IE
+			expect(overlay._image.style.zIndex).to.eql('10');
 		});
 
 		it('should use the z-index specified in options', () => {
 			const overlay = imageOverlay('', imageBounds, {zIndex: 20});
 			overlay.addTo(map);
-			expect(overlay._image.style.zIndex).to.eql('20'); // Number type in IE
+			expect(overlay._image.style.zIndex).to.eql('20');
 		});
 
 		it('should be fluent', () => {
diff --git a/spec/suites/layer/PopupSpec.js b/spec/suites/layer/PopupSpec.js
index 6ee060822..c919ddf67 100644
--- a/spec/suites/layer/PopupSpec.js
+++ b/spec/suites/layer/PopupSpec.js
@@ -103,7 +103,7 @@ describe('Popup', () => {
 		// toggle popup on marker1
 		group.fire('click', {
 			latlng: center,
-			layer: marker1
+			propagatedFrom: marker1
 		});
 		expect(map.hasLayer(group._popup)).to.be.true;
 		expect(group._popup._contentNode.innerHTML).to.equal('I\'m marker 1.');
@@ -111,7 +111,7 @@ describe('Popup', () => {
 		// toggle popup on marker2
 		group.fire('click', {
 			latlng: [54.6, 38.2],
-			layer: marker2
+			propagatedFrom: marker2
 		});
 		expect(map.hasLayer(group._popup)).to.be.true;
 		expect(group._popup._contentNode.innerHTML).to.equal('I\'m marker 2.');
@@ -133,7 +133,7 @@ describe('Popup', () => {
 		// toggle popup on marker1
 		group.fire('click', {
 			latlng: center,
-			layer: marker1
+			propagatedFrom: marker1
 		});
 		expect(map.hasLayer(group._popup)).to.be.true;
 		expect(group._popup._contentNode.innerHTML).to.equal('I\'m marker 1.');
@@ -141,7 +141,7 @@ describe('Popup', () => {
 		// toggle popup on marker2
 		group.fire('click', {
 			latlng: [54.6, 38.2],
-			layer: marker2
+			propagatedFrom: marker2
 		});
 		expect(map.hasLayer(group._popup)).to.be.true;
 		expect(group._popup._contentNode.innerHTML).to.equal('I\'m marker 2.');
diff --git a/spec/suites/layer/VideoOverlaySpec.js b/spec/suites/layer/VideoOverlaySpec.js
index b4cd7a6ba..010de3270 100644
--- a/spec/suites/layer/VideoOverlaySpec.js
+++ b/spec/suites/layer/VideoOverlaySpec.js
@@ -17,10 +17,7 @@ describe('VideoOverlay', () => {
 		removeMapContainer(map, container);
 	});
 
-
-	it('create VideoOverlay', function () {
-		this.timeout(10000); // This test takes longer than usual in IE
-
+	it('create VideoOverlay', () => {
 		const videoUrls = [
 			'https://www.mapbox.com/bites/00188/patricia_nasa.webm',
 			'https://www.mapbox.com/bites/00188/patricia_nasa.mp4'
diff --git a/spec/suites/layer/marker/Icon.DefaultSpec.js b/spec/suites/layer/marker/Icon.DefaultSpec.js
index 82866a8d1..9ba59fec6 100644
--- a/spec/suites/layer/marker/Icon.DefaultSpec.js
+++ b/spec/suites/layer/marker/Icon.DefaultSpec.js
@@ -33,7 +33,7 @@ describe('Icon.Default', () => {
 		[ // valid
 			'url("http://localhost:8000/base/dist/images/marker-icon.png")',  // Firefox
 			'url(\'http://localhost:8000/base/dist/images/marker-icon.png\')',
-			'url(http://localhost:8000/base/dist/images/marker-icon.png)',    // IE, Edge
+			'url(http://localhost:8000/base/dist/images/marker-icon.png)'
 		].map(stripUrl).forEach((str) => { expect(str).to.equal(properPath); });
 
 		[ // invalid
diff --git a/spec/suites/layer/tile/TileLayerSpec.js b/spec/suites/layer/tile/TileLayerSpec.js
index 3bdd3a4a2..27a6a516c 100644
--- a/spec/suites/layer/tile/TileLayerSpec.js
+++ b/spec/suites/layer/tile/TileLayerSpec.js
@@ -1,5 +1,5 @@
 import {expect} from 'chai';
-import {Browser, CRS, DomUtil, Map, TileLayer, Util, LatLng} from 'leaflet';
+import {Browser, CRS, Map, TileLayer, Util, LatLng} from 'leaflet';
 import sinon from 'sinon';
 import {createContainer, removeMapContainer} from '../../SpecHelper.js';
 
@@ -442,8 +442,7 @@ describe('TileLayer', () => {
 		});
 	});
 
-	const _describe = 'crossOrigin' in DomUtil.create('img') ? describe : describe.skip; // skip in IE<11
-	_describe('crossOrigin option', () => {
+	describe('crossOrigin option', () => {
 		beforeEach(() => {
 			map.setView([0, 0], 2);
 		});
diff --git a/spec/suites/layer/vector/CircleSpec.js b/spec/suites/layer/vector/CircleSpec.js
index 944f8c99a..8045208fc 100644
--- a/spec/suites/layer/vector/CircleSpec.js
+++ b/spec/suites/layer/vector/CircleSpec.js
@@ -21,13 +21,6 @@ describe('Circle', () => {
 			const circle = new Circle([0, 0]);
 			expect(circle.getRadius()).to.eql(10);
 		});
-
-		it('throws error if radius is NaN', () => {
-			expect(() => {
-				new Circle([0, 0], NaN);
-			}).to.throw('Circle radius cannot be NaN');
-		});
-
 	});
 
 	describe('#getBounds', () => {
diff --git a/src/control/Control.Layers.js b/src/control/Control.Layers.js
index e701e3be1..b0421c2fa 100644
--- a/src/control/Control.Layers.js
+++ b/src/control/Control.Layers.js
@@ -188,9 +188,6 @@ export const Layers = Control.extend({
 		container = this._container = DomUtil.create('div', className),
 		collapsed = this.options.collapsed;
 
-		// makes this work on IE touch devices by stopping it from firing a mouseout event when the touch is released
-		container.setAttribute('aria-haspopup', true);
-
 		DomEvent.disableClickPropagation(container);
 		DomEvent.disableScrollPropagation(container);
 
diff --git a/src/core/Events.js b/src/core/Events.js
index 97882d704..9d48b944c 100644
--- a/src/core/Events.js
+++ b/src/core/Events.js
@@ -296,7 +296,6 @@ export const Events = {
 	_propagateEvent(e) {
 		for (const p of Object.values(this._eventParents ?? {})) {
 			p.fire(e.type, {
-				layer: e.target,
 				propagatedFrom: e.target,
 				...e
 			}, true);
diff --git a/src/core/Events.leafdoc b/src/core/Events.leafdoc
index c4d335dc5..966ce36bf 100644
--- a/src/core/Events.leafdoc
+++ b/src/core/Events.leafdoc
@@ -29,8 +29,6 @@ be the same as the `target`.
 @property propagatedFrom: Object
 For propagated events, the last object that propagated the event to its
 event parent.
-@property layer: Object
-**Deprecated.** The same as `propagatedFrom`.
 
 
 @miniclass KeyboardEvent (Event objects)
diff --git a/src/dom/DomEvent.js b/src/dom/DomEvent.js
index 5df8f3cb6..52b83215e 100644
--- a/src/dom/DomEvent.js
+++ b/src/dom/DomEvent.js
@@ -219,22 +219,10 @@ export function stop(e) {
 }
 
 // @function getPropagationPath(ev: DOMEvent): Array
-// Compatibility polyfill for [`Event.composedPath()`](https://developer.mozilla.org/en-US/docs/Web/API/Event/composedPath).
 // Returns an array containing the `HTMLElement`s that the given DOM event
 // should propagate to (if not stopped).
 export function getPropagationPath(ev) {
-	if (ev.composedPath) {
-		return ev.composedPath();
-	}
-
-	const path = [];
-	let el = ev.target;
-
-	while (el) {
-		path.push(el);
-		el = el.parentNode;
-	}
-	return path;
+	return ev.composedPath();
 }
 
 
@@ -278,9 +266,6 @@ export function getWheelDelta(e) {
 		(e.deltaY && e.deltaMode === 1) ? -e.deltaY * 20 : // Lines
 		(e.deltaY && e.deltaMode === 2) ? -e.deltaY * 60 : // Pages
 		(e.deltaX || e.deltaZ) ? 0 :	// Skip horizontal/depth wheel events
-		e.wheelDelta ? (e.wheelDeltaY || e.wheelDelta) / 2 : // Legacy IE pixels
-		(e.detail && Math.abs(e.detail) < 32765) ? -e.detail * 20 : // Legacy Moz lines
-		e.detail ? e.detail / -32765 * 60 : // Legacy Moz pages
 		0;
 }
 
diff --git a/src/dom/Draggable.js b/src/dom/Draggable.js
index ff18add37..bd58b33e9 100644
--- a/src/dom/Draggable.js
+++ b/src/dom/Draggable.js
@@ -154,11 +154,6 @@ export const Draggable = Evented.extend({
 			document.body.classList.add('leaflet-dragging');
 
 			this._lastTarget = e.target ?? e.srcElement;
-			// IE and Edge do not give the <use> element, so fetch it
-			// if necessary
-			if (window.SVGElementInstance && this._lastTarget instanceof window.SVGElementInstance) {
-				this._lastTarget = this._lastTarget.correspondingUseElement;
-			}
 			this._lastTarget.classList.add('leaflet-drag-target');
 		}
 
diff --git a/src/geo/crs/CRS.EPSG4326.js b/src/geo/crs/CRS.EPSG4326.js
index 1564fa505..5bd198188 100644
--- a/src/geo/crs/CRS.EPSG4326.js
+++ b/src/geo/crs/CRS.EPSG4326.js
@@ -8,9 +8,8 @@ import {toTransformation} from '../../geometry/Transformation.js';
  *
  * A common CRS among GIS enthusiasts. Uses simple Equirectangular projection.
  *
- * Leaflet 1.0.x complies with the [TMS coordinate scheme for EPSG:4326](https://wiki.osgeo.org/wiki/Tile_Map_Service_Specification#global-geodetic),
- * which is a breaking change from 0.7.x behaviour.  If you are using a `TileLayer`
- * with this CRS, ensure that there are two 256x256 pixel tiles covering the
+ * Leaflet complies with the [TMS coordinate scheme for EPSG:4326](https://wiki.osgeo.org/wiki/Tile_Map_Service_Specification#global-geodetic).
+ * If you are using a `TileLayer` with this CRS, ensure that there are two 256x256 pixel tiles covering the
  * whole earth at zoom level zero, and that the tile coordinate origin is (-180,+90),
  * or (-180,-90) for `TileLayer`s with [the `tms` option](#tilelayer-tms) set.
  */
diff --git a/src/layer/Popup.js b/src/layer/Popup.js
index c25b97f94..f3d86067c 100644
--- a/src/layer/Popup.js
+++ b/src/layer/Popup.js
@@ -500,7 +500,7 @@ Layer.include({
 		// prevent map click
 		DomEvent.stop(e);
 
-		const target = e.layer ?? e.target;
+		const target = e.propagatedFrom ?? e.target;
 		if (this._popup._source === target && !(target instanceof Path)) {
 			// treat it like a marker and figure out
 			// if we should toggle it open/closed
diff --git a/src/layer/Tooltip.js b/src/layer/Tooltip.js
index 3a79f4bbc..9ca64574e 100644
--- a/src/layer/Tooltip.js
+++ b/src/layer/Tooltip.js
@@ -444,7 +444,7 @@ Layer.include({
 			return;
 		}
 
-		this._tooltip._source = e.layer ?? e.target;
+		this._tooltip._source = e.propagatedFrom ?? e.target;
 
 		this.openTooltip(this._tooltip.options.sticky ? e.latlng : undefined);
 	},
diff --git a/src/layer/marker/Icon.Default.js b/src/layer/marker/Icon.Default.js
index c27100b12..8091e10ec 100644
--- a/src/layer/marker/Icon.Default.js
+++ b/src/layer/marker/Icon.Default.js
@@ -31,7 +31,8 @@ export const IconDefault = Icon.extend({
 	},
 
 	_getIconUrl(name) {
-		if (typeof IconDefault.imagePath !== 'string') {	// Deprecated, backwards-compatibility only
+		// only detect once
+		if (!IconDefault.imagePath) {
 			IconDefault.imagePath = this._detectIconPath();
 		}
 
diff --git a/src/layer/vector/Circle.js b/src/layer/vector/Circle.js
index 658e4d261..296dd35e5 100644
--- a/src/layer/vector/Circle.js
+++ b/src/layer/vector/Circle.js
@@ -24,11 +24,7 @@ import {Earth} from '../../geo/crs/CRS.Earth.js';
 
 export const Circle = CircleMarker.extend({
 
-	initialize(latlng, options, legacyOptions) {
-		if (typeof options === 'number') {
-			// Backwards compatibility with 0.7.x factory (latlng, radius, options?)
-			options = {...legacyOptions, radius: options};
-		}
+	initialize(latlng, options) {
 		Util.setOptions(this, options);
 		this._latlng = toLatLng(latlng);
 
@@ -104,10 +100,6 @@ export const Circle = CircleMarker.extend({
 // @factory L.circle(latlng: LatLng, options?: Circle options)
 // Instantiates a circle object given a geographical point, and an options object
 // which contains the circle radius.
-// @alternative
-// @factory L.circle(latlng: LatLng, radius: Number, options?: Circle options)
-// Obsolete way of instantiating a circle, for compatibility with 0.7.x code.
-// Do not use in new applications or plugins.
 export function circle(latlng, options, legacyOptions) {
 	return new Circle(latlng, options, legacyOptions);
 }