diff --git a/components/button/__tests__/delay-timer.test.tsx b/components/button/__tests__/delay-timer.test.tsx
new file mode 100644
index 0000000000..c0fb924051
--- /dev/null
+++ b/components/button/__tests__/delay-timer.test.tsx
@@ -0,0 +1,89 @@
+import React, { useState } from 'react';
+import { mount } from 'enzyme';
+import { act } from 'react-dom/test-utils';
+import Button from '../button';
+
+const specialDelay = 9529;
+const Content = () => {
+  const [loading, setLoading] = useState(false);
+  const toggleLoading = () => {
+    setLoading(!loading);
+  };
+
+  const [visible, setVisible] = useState(true);
+  const toggleVisible = () => {
+    setVisible(!visible);
+  };
+
+  return (
+    <div>
+      <button type="button" id="toggle_loading" onClick={toggleLoading}>
+        Toggle Loading
+      </button>
+      <button type="button" id="toggle_visible" onClick={toggleVisible}>
+        Toggle Visible
+      </button>
+      {visible && <Button type="text" loading={loading ? { delay: specialDelay } : false} />}
+    </div>
+  );
+};
+
+it('Delay loading timer in Button component', () => {
+  const otherTimer: any = 9528;
+  jest.spyOn(window, 'setTimeout').mockReturnValue(otherTimer);
+  jest.restoreAllMocks();
+
+  const wrapper = mount(<Content />);
+
+  const btnTimer: any = 9527;
+  jest.spyOn(window, 'setTimeout').mockReturnValue(btnTimer);
+  jest.spyOn(window, 'clearTimeout');
+  const setTimeoutMock = window.setTimeout as any as jest.Mock;
+  const clearTimeoutMock = window.clearTimeout as any as jest.Mock;
+
+  // other component may call setTimeout or clearTimeout
+  const setTimeoutCount = () => {
+    const items = setTimeoutMock.mock.calls.filter(item => item[1] === specialDelay);
+    return items.length;
+  };
+  const clearTimeoutCount = () => {
+    const items = clearTimeoutMock.mock.calls.filter(item => item[0] === btnTimer);
+    return items.length;
+  };
+
+  // switch loading state to true
+  wrapper.find('#toggle_loading').at(0).simulate('click');
+  expect(setTimeoutCount()).toBe(1);
+  expect(clearTimeoutCount()).toBe(0);
+
+  // trigger timer handler
+  act(() => {
+    setTimeoutMock.mock.calls[0][0]();
+  });
+  expect(setTimeoutCount()).toBe(1);
+  expect(clearTimeoutCount()).toBe(0);
+
+  // switch loading state to false
+  wrapper.find('#toggle_loading').at(0).simulate('click');
+  expect(setTimeoutCount()).toBe(1);
+  expect(clearTimeoutCount()).toBe(0);
+
+  // switch loading state to true
+  wrapper.find('#toggle_loading').at(0).simulate('click');
+  expect(setTimeoutCount()).toBe(2);
+  expect(clearTimeoutCount()).toBe(0);
+
+  // switch loading state to false
+  wrapper.find('#toggle_loading').at(0).simulate('click');
+  expect(setTimeoutCount()).toBe(2);
+  expect(clearTimeoutCount()).toBe(1);
+
+  // switch loading state to true
+  wrapper.find('#toggle_loading').at(0).simulate('click');
+  // remove Button component
+  wrapper.find('#toggle_visible').at(0).simulate('click');
+  expect(setTimeoutCount()).toBe(3);
+  expect(clearTimeoutCount()).toBe(2);
+
+  jest.restoreAllMocks();
+});
diff --git a/components/button/button.tsx b/components/button/button.tsx
index 9bc2b2423f..215025ba7b 100644
--- a/components/button/button.tsx
+++ b/components/button/button.tsx
@@ -156,7 +156,6 @@ const InternalButton: React.ForwardRefRenderFunction<unknown, ButtonProps> = (pr
   const [hasTwoCNChar, setHasTwoCNChar] = React.useState(false);
   const { getPrefixCls, autoInsertSpaceInButton, direction } = React.useContext(ConfigContext);
   const buttonRef = (ref as any) || React.createRef<HTMLElement>();
-  const delayTimeoutRef = React.useRef<number>();
 
   const isNeedInserted = () =>
     React.Children.count(children) === 1 && !icon && !isUnborderedButtonType(type);
@@ -181,14 +180,25 @@ const InternalButton: React.ForwardRefRenderFunction<unknown, ButtonProps> = (pr
     typeof loading === 'object' && loading.delay ? loading.delay || true : !!loading;
 
   React.useEffect(() => {
-    clearTimeout(delayTimeoutRef.current);
+    let delayTimer: number | null = null;
+
     if (typeof loadingOrDelay === 'number') {
-      delayTimeoutRef.current = window.setTimeout(() => {
+      delayTimer = window.setTimeout(() => {
+        delayTimer = null;
         setLoading(loadingOrDelay);
       }, loadingOrDelay);
     } else {
       setLoading(loadingOrDelay);
     }
+
+    return () => {
+      if (delayTimer) {
+        // in order to not perform a React state update on an unmounted component
+        // and clear timer after 'loadingOrDelay' updated.
+        window.clearTimeout(delayTimer);
+        delayTimer = null;
+      }
+    };
   }, [loadingOrDelay]);
 
   React.useEffect(fixTwoCNChar, [buttonRef]);
diff --git a/components/button/style/index.less b/components/button/style/index.less
index 357ca5ba87..cdb67c8d0e 100644
--- a/components/button/style/index.less
+++ b/components/button/style/index.less
@@ -256,7 +256,7 @@
     letter-spacing: 0.34em;
   }
 
-  &-block {
+  &&-block {
     width: 100%;
   }
 
diff --git a/components/tooltip/__tests__/tooltip.test.js b/components/tooltip/__tests__/tooltip.test.js
index ad26de36b0..2eb67f1356 100644
--- a/components/tooltip/__tests__/tooltip.test.js
+++ b/components/tooltip/__tests__/tooltip.test.js
@@ -346,4 +346,22 @@ describe('Tooltip', () => {
     );
     expect(wrapper.find('.ant-tooltip-inner').getDOMNode().style.color).toBe('red');
   });
+
+  it('should work with loading switch', () => {
+    const onVisibleChange = jest.fn();
+    const wrapper = mount(
+      <Tooltip
+        title="loading tips"
+        mouseEnterDelay={0}
+        mouseLeaveDelay={0}
+        onVisibleChange={onVisibleChange}
+      >
+        <Switch loading defaultChecked />
+      </Tooltip>,
+    );
+    const wrapperEl = wrapper.find('.ant-tooltip-disabled-compatible-wrapper');
+    expect(wrapperEl).toHaveLength(1);
+    wrapper.find('span').first().simulate('mouseenter');
+    expect(onVisibleChange).toHaveBeenLastCalledWith(true);
+  });
 });
diff --git a/components/tooltip/index.tsx b/components/tooltip/index.tsx
index 0e8b6e0562..6c8e103390 100644
--- a/components/tooltip/index.tsx
+++ b/components/tooltip/index.tsx
@@ -85,10 +85,8 @@ const PresetColorRegex = new RegExp(`^(${PresetColorTypes.join('|')})(-inverse)?
 function getDisabledCompatibleChildren(element: React.ReactElement<any>, prefixCls: string) {
   const elementType = element.type as any;
   if (
-    (elementType.__ANT_BUTTON === true ||
-      elementType.__ANT_SWITCH === true ||
-      element.type === 'button') &&
-    element.props.disabled
+    ((elementType.__ANT_BUTTON === true || element.type === 'button') && element.props.disabled) ||
+    (elementType.__ANT_SWITCH === true && (element.props.disabled || element.props.loading))
   ) {
     // Pick some layout related style properties up to span
     // Prevent layout bugs like https://github.com/ant-design/ant-design/issues/5254
diff --git a/components/typography/Base/index.tsx b/components/typography/Base/index.tsx
index c3838330ba..c6eea42bf8 100644
--- a/components/typography/Base/index.tsx
+++ b/components/typography/Base/index.tsx
@@ -293,12 +293,14 @@ const Base = React.forwardRef((props: InternalBlockProps, ref: any) => {
     const textEle = typographyRef.current;
 
     if (enableEllipsis && cssEllipsis && textEle) {
-      const currentEllipsis = textEle.offsetWidth < textEle.scrollWidth;
+      const currentEllipsis = cssLineClamp
+        ? textEle.offsetHeight < textEle.scrollHeight
+        : textEle.offsetWidth < textEle.scrollWidth;
       if (isNativeEllipsis !== currentEllipsis) {
         setIsNativeEllipsis(currentEllipsis);
       }
     }
-  }, [enableEllipsis, cssEllipsis, children]);
+  }, [enableEllipsis, cssEllipsis, children, cssLineClamp]);
 
   // ========================== Tooltip ===========================
   const tooltipTitle = ellipsisConfig.tooltip === true ? children : ellipsisConfig.tooltip;
diff --git a/components/typography/__tests__/ellipsis.test.js b/components/typography/__tests__/ellipsis.test.js
index 372c206039..34173480db 100644
--- a/components/typography/__tests__/ellipsis.test.js
+++ b/components/typography/__tests__/ellipsis.test.js
@@ -277,4 +277,34 @@ describe('Typography.Ellipsis', () => {
     const tooltipWrapper = mount(<Base ellipsis={{ expandable: true, tooltip: 'little' }} />);
     expect(tooltipWrapper.find('.ant-typography').prop('aria-label')).toEqual('little');
   });
+
+  it('should display tooltip if line clamp', () => {
+    mockRectSpy = spyElementPrototypes(HTMLElement, {
+      scrollHeight: {
+        get() {
+          let html = this.innerHTML;
+          html = html.replace(/<[^>]*>/g, '');
+          const lines = Math.ceil(html.length / LINE_STR_COUNT);
+          return lines * 16;
+        },
+      },
+      offsetHeight: {
+        get: () => 32,
+      },
+      offsetWidth: {
+        get: () => 100,
+      },
+      scrollWidth: {
+        get: () => 100,
+      },
+    });
+
+    const wrapper = mount(
+      <Base ellipsis={{ tooltip: 'This is tooltip', rows: 2 }}>
+        Ant Design, a design language for background applications, is refined by Ant UED Team.
+      </Base>,
+    );
+    expect(wrapper.find('EllipsisTooltip').prop('isEllipsis')).toBeTruthy();
+    mockRectSpy.mockRestore();
+  });
 });
diff --git a/components/upload/Upload.tsx b/components/upload/Upload.tsx
index 628f36afd8..305caad216 100644
--- a/components/upload/Upload.tsx
+++ b/components/upload/Upload.tsx
@@ -322,7 +322,7 @@ const InternalUpload: React.ForwardRefRenderFunction<unknown, UploadProps> = (pr
     delete rcUploadProps.id;
   }
 
-  const renderUploadList = (button?: React.ReactNode) =>
+  const renderUploadList = (button?: React.ReactNode, buttonVisible?: boolean) =>
     showUploadList ? (
       <LocaleReceiver componentName="Upload" defaultLocale={defaultLocale.Upload}>
         {(locale: UploadLocale) => {
@@ -354,6 +354,7 @@ const InternalUpload: React.ForwardRefRenderFunction<unknown, UploadProps> = (pr
               isImageUrl={isImageUrl}
               progress={progress}
               appendAction={button}
+              appendActionVisible={buttonVisible}
               itemRender={itemRender}
             />
           );
@@ -400,8 +401,8 @@ const InternalUpload: React.ForwardRefRenderFunction<unknown, UploadProps> = (pr
     [`${prefixCls}-rtl`]: direction === 'rtl',
   });
 
-  const uploadButton = (
-    <div className={uploadButtonCls} style={children ? undefined : { display: 'none' }}>
+  const renderUploadButton = (uploadButtonStyle?: React.CSSProperties) => (
+    <div className={uploadButtonCls} style={uploadButtonStyle}>
       <RcUpload {...rcUploadProps} ref={upload} />
     </div>
   );
@@ -409,14 +410,14 @@ const InternalUpload: React.ForwardRefRenderFunction<unknown, UploadProps> = (pr
   if (listType === 'picture-card') {
     return (
       <span className={classNames(`${prefixCls}-picture-card-wrapper`, className)}>
-        {renderUploadList(uploadButton)}
+        {renderUploadList(renderUploadButton(), !!children)}
       </span>
     );
   }
 
   return (
     <span className={className}>
-      {uploadButton}
+      {renderUploadButton(children ? undefined : { display: 'none' })}
       {renderUploadList()}
     </span>
   );
diff --git a/components/upload/UploadList/index.tsx b/components/upload/UploadList/index.tsx
index 89955c2127..11f7083ea6 100644
--- a/components/upload/UploadList/index.tsx
+++ b/components/upload/UploadList/index.tsx
@@ -42,6 +42,7 @@ const InternalUploadList: React.ForwardRefRenderFunction<unknown, UploadListProp
     downloadIcon,
     progress,
     appendAction,
+    appendActionVisible,
     itemRender,
   },
   ref,
@@ -225,12 +226,14 @@ const InternalUploadList: React.ForwardRefRenderFunction<unknown, UploadListProp
 
       {/* Append action */}
       {appendAction && (
-        <CSSMotion {...motionConfig}>
+        <CSSMotion {...motionConfig} visible={appendActionVisible} forceRender>
           {({ className: motionClassName, style: motionStyle }) =>
             cloneElement(appendAction, oriProps => ({
               className: classNames(oriProps.className, motionClassName),
               style: {
                 ...motionStyle,
+                // prevent the element has hover css pseudo-class that may cause animation to end prematurely.
+                pointerEvents: motionClassName ? 'none' : undefined,
                 ...oriProps.style,
               },
             }))
@@ -254,6 +257,7 @@ UploadList.defaultProps = {
   showRemoveIcon: true,
   showDownloadIcon: false,
   showPreviewIcon: true,
+  appendActionVisible: true,
   previewFile: previewImage,
   isImageUrl,
 };
diff --git a/components/upload/__tests__/upload.test.js b/components/upload/__tests__/upload.test.js
index c096327999..71865b951e 100644
--- a/components/upload/__tests__/upload.test.js
+++ b/components/upload/__tests__/upload.test.js
@@ -867,4 +867,26 @@ describe('Upload', () => {
 
     expect(onChange.mock.calls[0][0].fileList).toHaveLength(1);
   });
+
+  // https://github.com/ant-design/ant-design/issues/33819
+  it('should show the animation of the upload children leaving when the upload children becomes null', async () => {
+    const wrapper = mount(
+      <Upload listType="picture-card">
+        <button type="button">upload</button>
+      </Upload>,
+    );
+    wrapper.setProps({ children: null });
+    expect(wrapper.find('.ant-upload-select-picture-card').getDOMNode().style.display).not.toBe(
+      'none',
+    );
+    await act(async () => {
+      await sleep(100);
+      wrapper
+        .find('.ant-upload-select-picture-card')
+        .getDOMNode()
+        .dispatchEvent(new Event('animationend'));
+      await sleep(20);
+    });
+    expect(wrapper.find('.ant-upload-select-picture-card').getDOMNode().style.display).toBe('none');
+  });
 });
diff --git a/components/upload/interface.tsx b/components/upload/interface.tsx
index 7c11a8dd22..ff47c3c1b6 100755
--- a/components/upload/interface.tsx
+++ b/components/upload/interface.tsx
@@ -155,5 +155,6 @@ export interface UploadListProps<T = any> {
   iconRender?: (file: UploadFile<T>, listType?: UploadListType) => React.ReactNode;
   isImageUrl?: (file: UploadFile) => boolean;
   appendAction?: React.ReactNode;
+  appendActionVisible?: boolean;
   itemRender?: ItemRender<T>;
 }