diff --git a/packages/ui-elements/package.json b/packages/ui-elements/package.json
index e08f04fb6f..869b976f00 100644
--- a/packages/ui-elements/package.json
+++ b/packages/ui-elements/package.json
@@ -22,7 +22,8 @@
         "lint": "eslint 'src/**/*.js'",
         "lint:fix": "eslint 'src/**/*.js' --fix",
         "storybook": "storybook dev -p 6006",
-        "build-storybook": "storybook build"
+        "build-storybook": "storybook build",
+        "test": "node --test src/components/**/*.test.mjs"
     },
     "author": "",
     "license": "ISC",
diff --git a/packages/ui-elements/src/components/ActionButton/ActionButton.js b/packages/ui-elements/src/components/ActionButton/ActionButton.js
index f6dfb25f7e..64c6a8e541 100644
--- a/packages/ui-elements/src/components/ActionButton/ActionButton.js
+++ b/packages/ui-elements/src/components/ActionButton/ActionButton.js
@@ -2,16 +2,7 @@ import React, { forwardRef } from 'react';
 import PropTypes from 'prop-types';
 import { Button } from '../Button';
 import { Icon } from '../Icon';
-
-const getSize = ({ small, large, size }) => {
-  if (small) {
-    return '1.25rem';
-  }
-  if (large) {
-    return '1.75rem';
-  }
-  return size || '1.5rem';
-};
+import getIconSize from './getIconSize';
 
 const ActionButton = forwardRef(
   (
@@ -27,7 +18,7 @@ const ActionButton = forwardRef(
   ) => (
     <Button ref={ref} square size={size} type={color} {...props}>
       {children}
-      <Icon name={icon} size={getSize(iconSize)} />
+      <Icon name={icon} size={getIconSize(iconSize, size)} />
     </Button>
   )
 );
@@ -41,6 +32,15 @@ ActionButton.propTypes = {
     PropTypes.node,
   ]),
   size: PropTypes.oneOf(['small', 'medium', 'large']),
+  iconSize: PropTypes.oneOfType([
+    PropTypes.string,
+    PropTypes.shape({
+      small: PropTypes.bool,
+      large: PropTypes.bool,
+      size: PropTypes.string,
+    }),
+  ]),
 };
 
+export { getIconSize };
 export default ActionButton;
diff --git a/packages/ui-elements/src/components/ActionButton/ActionButton.test.mjs b/packages/ui-elements/src/components/ActionButton/ActionButton.test.mjs
new file mode 100644
index 0000000000..0670b2414d
--- /dev/null
+++ b/packages/ui-elements/src/components/ActionButton/ActionButton.test.mjs
@@ -0,0 +1,36 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import getIconSize from './getIconSize.js';
+
+test('ActionButton: derives small icon size (1rem) for small action button to prevent container overflow', () => {
+  assert.strictEqual(getIconSize({}, 'small'), '1rem');
+});
+
+test('ActionButton: derives medium icon size (1.25rem) by default', () => {
+  assert.strictEqual(getIconSize({}, 'medium'), '1.25rem');
+  assert.strictEqual(getIconSize(), '1.25rem');
+});
+
+test('ActionButton: derives large icon size (1.75rem) for large action button', () => {
+  assert.strictEqual(getIconSize({}, 'large'), '1.75rem');
+});
+
+test('ActionButton: supports named iconSize strings ("small", "medium", "large")', () => {
+  assert.strictEqual(getIconSize('small', 'medium'), '1rem');
+  assert.strictEqual(getIconSize('medium', 'medium'), '1.25rem');
+  assert.strictEqual(getIconSize('large', 'medium'), '1.75rem');
+});
+
+test('ActionButton: supports custom iconSize css length string', () => {
+  assert.strictEqual(getIconSize('1.4rem', 'medium'), '1.4rem');
+  assert.strictEqual(getIconSize('18px', 'small'), '18px');
+});
+
+test('ActionButton: supports legacy object syntax { small: true } and { large: true }', () => {
+  assert.strictEqual(getIconSize({ small: true }), '1rem');
+  assert.strictEqual(getIconSize({ large: true }), '1.75rem');
+});
+
+test('ActionButton: supports explicit size property in iconSize object { size: "1.3rem" }', () => {
+  assert.strictEqual(getIconSize({ size: '1.3rem' }), '1.3rem');
+});
diff --git a/packages/ui-elements/src/components/ActionButton/getIconSize.js b/packages/ui-elements/src/components/ActionButton/getIconSize.js
new file mode 100644
index 0000000000..6f00a8cabb
--- /dev/null
+++ b/packages/ui-elements/src/components/ActionButton/getIconSize.js
@@ -0,0 +1,35 @@
+const getIconSize = (iconSize, buttonSize) => {
+  if (typeof iconSize === 'string') {
+    if (iconSize === 'small') {
+      return '1rem';
+    }
+    if (iconSize === 'medium') {
+      return '1.25rem';
+    }
+    if (iconSize === 'large') {
+      return '1.75rem';
+    }
+    return iconSize;
+  }
+  if (iconSize && typeof iconSize === 'object') {
+    if (iconSize.size) {
+      return iconSize.size;
+    }
+    if (iconSize.small) {
+      return '1rem';
+    }
+    if (iconSize.large) {
+      return '1.75rem';
+    }
+  }
+  if (buttonSize === 'small') {
+    return '1rem';
+  }
+  if (buttonSize === 'large') {
+    return '1.75rem';
+  }
+  return '1.25rem';
+};
+
+export default getIconSize;
+
diff --git a/packages/ui-elements/src/components/Tooltip/Tooltip.js b/packages/ui-elements/src/components/Tooltip/Tooltip.js
index cc3eab6801..7b1436b17d 100644
--- a/packages/ui-elements/src/components/Tooltip/Tooltip.js
+++ b/packages/ui-elements/src/components/Tooltip/Tooltip.js
@@ -1,11 +1,20 @@
-import React, { useState } from 'react';
+import React, { useState, useRef, useEffect } from 'react';
 import { css } from '@emotion/react';
+import PropTypes from 'prop-types';
 import { Box } from '../Box';
 import getToolTipStyles from './Tooltip.styles';
 import { useTheme } from '../../hooks';
 
-const Tooltip = ({ children, text, position }) => {
+const Tooltip = ({
+  children,
+  text,
+  position = 'top',
+  className = '',
+  style = {},
+  ...props
+}) => {
   const [isTooltipVisible, setTooltipVisible] = useState(false);
+  const touchTimerRef = useRef(null);
   const { theme } = useTheme();
   const styles = getToolTipStyles(theme, position);
 
@@ -17,35 +26,78 @@ const Tooltip = ({ children, text, position }) => {
     setTooltipVisible(false);
   };
 
-  let touchTimer;
+  const handleFocus = () => {
+    setTooltipVisible(true);
+  };
+
+  const handleBlur = () => {
+    setTooltipVisible(false);
+  };
+
+  const handleKeyDown = (event) => {
+    if (event.key === 'Escape') {
+      setTooltipVisible(false);
+    }
+  };
 
   const handleTouchStart = () => {
-    touchTimer = setTimeout(() => {
+    touchTimerRef.current = setTimeout(() => {
       setTooltipVisible(true);
     }, 500);
   };
 
   const handleTouchEnd = () => {
-    clearTimeout(touchTimer);
+    if (touchTimerRef.current) {
+      clearTimeout(touchTimerRef.current);
+      touchTimerRef.current = null;
+    }
     setTooltipVisible(false);
   };
 
+  useEffect(
+    () => () => {
+      if (touchTimerRef.current) {
+        clearTimeout(touchTimerRef.current);
+      }
+    },
+    []
+  );
+
+  const hasText = Boolean(
+    text && (typeof text === 'string' ? text.trim().length > 0 : true)
+  );
+  const formattedText =
+    typeof text === 'string' && text.length > 0
+      ? text.charAt(0).toUpperCase() + text.slice(1)
+      : text;
+
   return (
     <Box
       is="span"
+      className={className}
+      style={style}
       onMouseEnter={handleMouseEnter}
       onMouseLeave={handleMouseLeave}
+      onFocus={handleFocus}
+      onBlur={handleBlur}
+      onKeyDown={handleKeyDown}
       onTouchStart={handleTouchStart}
       onTouchEnd={handleTouchEnd}
       css={css`
         position: relative;
         display: inline-block;
       `}
+      {...props}
     >
       {children}
-      {isTooltipVisible && (
-        <Box is="span" css={styles.tooltip}>
-          {text.charAt(0).toUpperCase() + text.slice(1)}
+      {hasText && isTooltipVisible && (
+        <Box
+          is="span"
+          role="tooltip"
+          aria-hidden={!isTooltipVisible}
+          css={styles.tooltip}
+        >
+          {formattedText}
           <Box is="span" css={styles.tooltipArrow} />
         </Box>
       )}
@@ -53,4 +105,12 @@ const Tooltip = ({ children, text, position }) => {
   );
 };
 
+Tooltip.propTypes = {
+  children: PropTypes.node,
+  text: PropTypes.node,
+  position: PropTypes.oneOf(['top', 'bottom', 'down']),
+  className: PropTypes.string,
+  style: PropTypes.object,
+};
+
 export default Tooltip;
diff --git a/packages/ui-elements/src/components/Tooltip/Tooltip.styles.js b/packages/ui-elements/src/components/Tooltip/Tooltip.styles.js
index 824eec5d49..7fec027b38 100644
--- a/packages/ui-elements/src/components/Tooltip/Tooltip.styles.js
+++ b/packages/ui-elements/src/components/Tooltip/Tooltip.styles.js
@@ -1,10 +1,12 @@
 import { css } from '@emotion/react';
 
-const getTooltipStyles = (theme, position) => {
+const getTooltipStyles = (theme, position = 'top') => {
+  const isBottom = position === 'bottom' || position === 'down';
+
   const styles = {
     tooltip: css`
       position: absolute;
-      left: 64%;
+      left: 50%;
       transform: translateX(-50%);
       background-color: ${theme.invertedColors.secondary};
       color: ${theme.invertedColors.secondaryForeground};
@@ -16,22 +18,32 @@ const getTooltipStyles = (theme, position) => {
       font-weight: 500;
       white-space: nowrap;
       font-family: sans-serif;
-      top: ${position === 'top' ? 'calc(-100% - 20px)' : 'calc(100% + 10px)'};
+      pointer-events: none;
+      ${isBottom
+        ? css`
+            top: calc(100% + 8px);
+          `
+        : css`
+            bottom: calc(100% + 8px);
+          `}
     `,
     tooltipArrow: css`
       content: '';
       position: absolute;
       left: 50%;
-      margin-left: -4px;
       border-width: 6px;
       border-style: solid;
       border-color: ${theme.invertedColors.secondary} transparent transparent
         transparent;
-      top: ${position === 'top' ? '100%' : 'auto'};
-      bottom: ${position === 'bottom' ? '100%' : 'auto'};
-      transform: ${position === 'bottom'
-        ? 'translateX(-50%) rotate(180deg)'
-        : 'translateX(-50%)'};
+      ${isBottom
+        ? css`
+            bottom: 100%;
+            transform: translateX(-50%) rotate(180deg);
+          `
+        : css`
+            top: 100%;
+            transform: translateX(-50%);
+          `}
     `,
   };
 
diff --git a/packages/ui-elements/src/components/Tooltip/Tooltip.styles.test.mjs b/packages/ui-elements/src/components/Tooltip/Tooltip.styles.test.mjs
new file mode 100644
index 0000000000..aa4722f332
--- /dev/null
+++ b/packages/ui-elements/src/components/Tooltip/Tooltip.styles.test.mjs
@@ -0,0 +1,74 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import getTooltipStyles from './Tooltip.styles.js';
+
+const mockTheme = {
+  radius: '4px',
+  invertedColors: {
+    secondary: '#1f2328',
+    secondaryForeground: '#ffffff',
+  },
+  zIndex: {
+    tooltip: 1400,
+  },
+};
+
+test('Tooltip.styles: centers tooltip horizontally with left: 50% and translateX(-50%)', () => {
+  const styles = getTooltipStyles(mockTheme, 'top');
+  const tooltipCss = styles.tooltip.styles;
+
+  assert.match(tooltipCss, /left:\s*50%/);
+  assert.match(tooltipCss, /transform:\s*translateX\(-50%\)/);
+  assert.doesNotMatch(
+    tooltipCss,
+    /left:\s*64%/,
+    'Should not use hardcoded 64% offset'
+  );
+});
+
+test('Tooltip.styles: positions top tooltip above anchor element', () => {
+  const styles = getTooltipStyles(mockTheme, 'top');
+  const tooltipCss = styles.tooltip.styles;
+  const arrowCss = styles.tooltipArrow.styles;
+
+  assert.match(tooltipCss, /bottom:\s*calc\(100%\s*\+\s*8px\)/);
+  assert.match(arrowCss, /top:\s*100%/);
+  assert.match(arrowCss, /transform:\s*translateX\(-50%\)/);
+});
+
+test('Tooltip.styles: positions bottom tooltip below anchor element with inverted arrow', () => {
+  const styles = getTooltipStyles(mockTheme, 'bottom');
+  const tooltipCss = styles.tooltip.styles;
+  const arrowCss = styles.tooltipArrow.styles;
+
+  assert.match(tooltipCss, /top:\s*calc\(100%\s*\+\s*8px\)/);
+  assert.match(arrowCss, /bottom:\s*100%/);
+  assert.match(arrowCss, /rotate\(180deg\)/);
+});
+
+test('Tooltip.styles: normalizes position "down" to behave identically to "bottom"', () => {
+  const downStyles = getTooltipStyles(mockTheme, 'down');
+  const bottomStyles = getTooltipStyles(mockTheme, 'bottom');
+
+  assert.strictEqual(downStyles.tooltip.styles, bottomStyles.tooltip.styles);
+  assert.strictEqual(
+    downStyles.tooltipArrow.styles,
+    bottomStyles.tooltipArrow.styles
+  );
+});
+
+test('Tooltip.styles: defaults to "top" position when position argument is omitted', () => {
+  const defaultStyles = getTooltipStyles(mockTheme);
+  const topStyles = getTooltipStyles(mockTheme, 'top');
+
+  assert.strictEqual(defaultStyles.tooltip.styles, topStyles.tooltip.styles);
+  assert.strictEqual(
+    defaultStyles.tooltipArrow.styles,
+    topStyles.tooltipArrow.styles
+  );
+});
+
+test('Tooltip.styles: includes pointer-events: none to avoid hover jitter and blocking clicks', () => {
+  const styles = getTooltipStyles(mockTheme, 'top');
+  assert.match(styles.tooltip.styles, /pointer-events:\s*none/);
+});
diff --git a/packages/ui-elements/src/components/Tooltip/Tooltip.test.mjs b/packages/ui-elements/src/components/Tooltip/Tooltip.test.mjs
new file mode 100644
index 0000000000..8ec1266610
--- /dev/null
+++ b/packages/ui-elements/src/components/Tooltip/Tooltip.test.mjs
@@ -0,0 +1,55 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+
+// Helper mirroring Tooltip's text formatting logic
+const formatTooltipText = (text) => {
+  const hasText = Boolean(
+    text && (typeof text === 'string' ? text.trim().length > 0 : true)
+  );
+  const formattedText =
+    typeof text === 'string' && text.length > 0
+      ? text.charAt(0).toUpperCase() + text.slice(1)
+      : text;
+
+  return { hasText, formattedText };
+};
+
+test('Tooltip formatTooltipText: safely handles undefined without throwing charAt TypeError', () => {
+  assert.doesNotThrow(() => {
+    const { hasText, formattedText } = formatTooltipText(undefined);
+    assert.strictEqual(hasText, false);
+    assert.strictEqual(formattedText, undefined);
+  });
+});
+
+test('Tooltip formatTooltipText: safely handles null without throwing TypeError', () => {
+  assert.doesNotThrow(() => {
+    const { hasText, formattedText } = formatTooltipText(null);
+    assert.strictEqual(hasText, false);
+    assert.strictEqual(formattedText, null);
+  });
+});
+
+test('Tooltip formatTooltipText: safely marks empty string as hasText = false', () => {
+  const { hasText, formattedText } = formatTooltipText('');
+  assert.strictEqual(hasText, false);
+  assert.strictEqual(formattedText, '');
+});
+
+test('Tooltip formatTooltipText: marks whitespace-only string as hasText = false', () => {
+  const { hasText } = formatTooltipText('   ');
+  assert.strictEqual(hasText, false);
+});
+
+test('Tooltip formatTooltipText: capitalizes first letter of valid tooltip string', () => {
+  const { hasText, formattedText } = formatTooltipText('pinned');
+  assert.strictEqual(hasText, true);
+  assert.strictEqual(formattedText, 'Pinned');
+});
+
+test('Tooltip formatTooltipText: preserves already capitalized string', () => {
+  const { hasText, formattedText } = formatTooltipText('Followers (3)');
+  assert.strictEqual(hasText, true);
+  assert.strictEqual(formattedText, 'Followers (3)');
+});
+