diff --git a/.prettierignore b/.prettierignore
new file mode 100644
index 00000000..0b27943e
--- /dev/null
+++ b/.prettierignore
@@ -0,0 +1 @@
+test/cases/tsx/src/counter.tsx
diff --git a/docs/components/banner-cta/banner-cta.test.ts b/docs/components/banner-cta/banner-cta.test.ts
index 4ca1ecdd..6767bb35 100644
--- a/docs/components/banner-cta/banner-cta.test.ts
+++ b/docs/components/banner-cta/banner-cta.test.ts
@@ -43,6 +43,7 @@ describe('Components/Banner CTA', () => {
 
   afterEach(() => {
     bannerCta.remove();
+    // @ts-expect-error
     bannerCta = undefined;
   });
 });
diff --git a/docs/components/banner-splash/banner-splash.test.ts b/docs/components/banner-splash/banner-splash.test.ts
index b5ad7a2b..c414b5b8 100644
--- a/docs/components/banner-splash/banner-splash.test.ts
+++ b/docs/components/banner-splash/banner-splash.test.ts
@@ -25,6 +25,7 @@ describe('Components/Banner Splash', () => {
 
   afterEach(() => {
     bannerSplash.remove();
+    // @ts-expect-error
     bannerSplash = undefined;
   });
 });
diff --git a/docs/components/capability-box/capability-box.test.ts b/docs/components/capability-box/capability-box.test.ts
index f335899b..485a9654 100644
--- a/docs/components/capability-box/capability-box.test.ts
+++ b/docs/components/capability-box/capability-box.test.ts
@@ -56,6 +56,7 @@ describe('Components/Capability Box', () => {
 
   afterEach(() => {
     capabilityBox.remove();
+    // @ts-ignore
     capabilityBox = undefined;
   });
 });
diff --git a/docs/components/ctc-block/ctc-block.ts b/docs/components/ctc-block/ctc-block.ts
index b2bb344b..f6d21950 100644
--- a/docs/components/ctc-block/ctc-block.ts
+++ b/docs/components/ctc-block/ctc-block.ts
@@ -7,11 +7,13 @@ const template = document.createElement('template');
 export default class CopyToClipboardBlock extends HTMLElement {
   selectCommandRunnerIdx;
   snippetContents;
+  root: ShadowRoot | null;
 
   constructor() {
     super();
     this.selectCommandRunnerIdx = 0;
     this.snippetContents = '';
+    this.root = null;
   }
 
   connectedCallback() {
@@ -48,23 +50,26 @@ export default class CopyToClipboardBlock extends HTMLElement {
         console.warn(`Unknown variant provided => ${variant}`);
       }
 
-      this.attachShadow({ mode: 'open' });
-      this.shadowRoot.appendChild(template.content.cloneNode(true));
-
-      switch (variant) {
-        case 'snippet':
-          this.shadowRoot
-            .querySelector('.copy-icon')
-            .addEventListener('click', this.copySnippetToClipboard.bind(this));
-          break;
-        case 'shell':
-          this.shadowRoot
-            .querySelector('.copy-icon')
-            .addEventListener('click', this.copyShellScriptToClipboard.bind(this));
-          break;
-      }
+      this.root = this.attachShadow({ mode: 'open' });
+
+      if (this.root) {
+        this.root.appendChild(template.content.cloneNode(true));
+
+        switch (variant) {
+          case 'snippet':
+            this.root
+              ?.querySelector('.copy-icon')
+              ?.addEventListener('click', this.copySnippetToClipboard.bind(this));
+            break;
+          case 'shell':
+            this.root
+              ?.querySelector('.copy-icon')
+              ?.addEventListener('click', this.copyShellScriptToClipboard.bind(this));
+            break;
+        }
 
-      this.shadowRoot.adoptedStyleSheets = [theme, sheet];
+        this.root.adoptedStyleSheets = [theme, sheet];
+      }
     }
   }
 
@@ -76,7 +81,12 @@ export default class CopyToClipboardBlock extends HTMLElement {
   }
 
   copyShellScriptToClipboard() {
-    const contents = this.getAttribute('paste-contents').trim();
+    const contents = this.getAttribute('paste-contents')?.trim();
+
+    if (!contents) {
+      console.warn('No content provided to copy to clipboard');
+      return;
+    }
 
     navigator.clipboard.writeText(contents);
     console.log('copying the following contents to your clipboard =>', contents);
diff --git a/docs/components/ctc-button/ctc-button.test.ts b/docs/components/ctc-button/ctc-button.test.ts
index b2cd9aee..79ba7670 100644
--- a/docs/components/ctc-button/ctc-button.test.ts
+++ b/docs/components/ctc-button/ctc-button.test.ts
@@ -18,14 +18,15 @@ describe('Components/Copy To Clipboard (Button)', () => {
     });
 
     it('should have an icon with the user provided content set', () => {
-      const icon = ctc.shadowRoot.querySelectorAll("[title='Copy to clipboard']");
+      const icon = ctc?.shadowRoot?.querySelectorAll("[title='Copy to clipboard']");
 
-      expect(icon.length).to.equal(1);
+      expect(icon?.length).to.equal(1);
     });
   });
 
   afterEach(() => {
     ctc.remove();
+    // @ts-expect-error
     ctc = undefined;
   });
 });
diff --git a/docs/components/ctc-button/ctc-button.tsx b/docs/components/ctc-button/ctc-button.tsx
index 29d108cb..aba4295c 100644
--- a/docs/components/ctc-button/ctc-button.tsx
+++ b/docs/components/ctc-button/ctc-button.tsx
@@ -8,20 +8,35 @@ template.innerHTML = `
 `;
 
 export default class CopyToClipboardButton extends HTMLElement {
+  root: ShadowRoot | null;
+
+  constructor() {
+    super();
+    this.root = null;
+  }
+
   connectedCallback() {
     // bail of out of SSR entirely
     if (!this.shadowRoot && typeof window !== 'undefined') {
-      this.attachShadow({ mode: 'open' });
-      this.shadowRoot.appendChild(template.content.cloneNode(true));
+      this.root = this.attachShadow({ mode: 'open' });
+
+      if (this.root) {
+        this.root.appendChild(template.content.cloneNode(true));
+
+        this.root.adoptedStyleSheets = [sheet];
 
-      this.shadowRoot.adoptedStyleSheets = [sheet];
+        this.root.getElementById('icon')?.addEventListener('click', () => {
+          const contents = this.getAttribute('content');
 
-      this.shadowRoot.getElementById('icon')?.addEventListener('click', () => {
-        const contents = this.getAttribute('content') ?? undefined;
+          if (!contents) {
+            console.warn('No content provided to copy to clipboard');
+            return;
+          }
 
-        navigator.clipboard.writeText(contents);
-        console.log('copying the following contents to your clipboard =>', contents);
-      });
+          navigator.clipboard.writeText(contents);
+          console.log('copying the following contents to your clipboard =>', contents);
+        });
+      }
     }
   }
 }
diff --git a/docs/components/feature-box/feature-box.test.ts b/docs/components/feature-box/feature-box.test.ts
index afff6f72..3c97ebe2 100644
--- a/docs/components/feature-box/feature-box.test.ts
+++ b/docs/components/feature-box/feature-box.test.ts
@@ -68,6 +68,7 @@ describe('Components/Feature Box', () => {
 
   afterEach(() => {
     featureBox.remove();
+    // @ts-expect-error
     featureBox = undefined;
   });
 });
diff --git a/docs/components/footer/footer.test.ts b/docs/components/footer/footer.test.ts
index 943af884..a0195353 100644
--- a/docs/components/footer/footer.test.ts
+++ b/docs/components/footer/footer.test.ts
@@ -38,6 +38,7 @@ describe('Components/Footer', () => {
 
   afterEach(() => {
     footer.remove();
+    // @ts-expect-error
     footer = undefined;
   });
 });
diff --git a/docs/components/header/header.test.ts b/docs/components/header/header.test.ts
index 8acf8c93..3bd0edcf 100644
--- a/docs/components/header/header.test.ts
+++ b/docs/components/header/header.test.ts
@@ -35,7 +35,7 @@ describe('Components/Header', () => {
     });
 
     it('should have an anchor tag with title attribute wrapping the logo', () => {
-      const anchor = header.querySelector("a[title='WCC Home Page']");
+      const anchor = header.querySelector("a[title='WCC Home Page']") as HTMLAnchorElement;
 
       expect(anchor).to.not.equal(undefined);
       expect(anchor.getAttribute('href')).to.equal('/');
@@ -56,22 +56,23 @@ describe('Components/Header', () => {
         const navItem = pages.find((nav) => nav.route === link.getAttribute('href'));
 
         expect(navItem).to.not.equal(undefined);
-        expect(navItem.data.order).to.equal((idx += 1));
-        expect(link.textContent).to.equal(navItem.label);
+        expect(navItem?.data.order).to.equal((idx += 1));
+        expect(link.textContent).to.equal(navItem?.label);
 
         // Home page doesn't have a title, for example
         // maybe a Greenwood bug?
-        if (navItem.title) {
-          expect(link.getAttribute('title')).to.equal(navItem.title);
+        if (navItem?.title) {
+          expect(link.getAttribute('title')).to.equal(navItem?.title);
         }
 
         // current route should display as active
-        if (navItem.route === CURRENT_ROUTE && link.getAttribute('class').includes('active')) {
-          activeRoute = navItem;
+        if (navItem?.route === CURRENT_ROUTE && link?.getAttribute('class')?.includes('active')) {
+          activeRoute = navItem as unknown as Page;
         }
       });
 
-      expect(activeRoute.route).to.equal(CURRENT_ROUTE);
+      // @ts-expect-error
+      expect(activeRoute?.route).to.equal(CURRENT_ROUTE);
     });
   });
 
@@ -106,33 +107,35 @@ describe('Components/Header', () => {
 
     it('should have the expected navigation links', () => {
       const links = header.querySelectorAll("nav[aria-label='Mobile'] ul li a");
-      let activeRoute: Page = undefined;
+      let activeRoute: Page;
 
       Array.from(links).forEach((link, idx) => {
         const navItem = pages.find((nav) => nav.route === link.getAttribute('href'));
 
         expect(navItem).to.not.equal(undefined);
-        expect(navItem.data.order).to.equal((idx += 1));
-        expect(link.textContent).to.equal(navItem.label);
+        expect(navItem?.data.order).to.equal((idx += 1));
+        expect(link.textContent).to.equal(navItem?.label);
 
         // Home page doesn't have a title, for example
         // maybe a Greenwood bug?
-        if (navItem.title) {
+        if (navItem?.title) {
           expect(link.getAttribute('title')).to.equal(navItem.title);
         }
 
         // current route should display as active
-        if (navItem.route === CURRENT_ROUTE && link.getAttribute('class').includes('active')) {
-          activeRoute = navItem;
+        if (navItem?.route === CURRENT_ROUTE && link?.getAttribute('class')?.includes('active')) {
+          activeRoute = navItem as unknown as Page;
         }
       });
 
-      expect(activeRoute.route).to.equal(CURRENT_ROUTE);
+      // @ts-expect-error
+      expect(activeRoute?.route).to.equal(CURRENT_ROUTE);
     });
   });
 
   afterEach(() => {
     header.remove();
+    // @ts-expect-error
     header = undefined;
   });
 
diff --git a/docs/components/sandbox/signal-counter.tsx b/docs/components/sandbox/signal-counter.tsx
index 116821fe..33f9761e 100644
--- a/docs/components/sandbox/signal-counter.tsx
+++ b/docs/components/sandbox/signal-counter.tsx
@@ -25,7 +25,9 @@ export default class SignalCounter extends HTMLElement {
       this.render();
     }
 
-    this.shadowRoot.adoptedStyleSheets = [sheet];
+    if (this.shadowRoot) {
+      this.shadowRoot.adoptedStyleSheets = [sheet];
+    }
   }
 
   increment() {
diff --git a/docs/components/side-nav/side-nav.test.ts b/docs/components/side-nav/side-nav.test.ts
index b27252e6..8d478008 100644
--- a/docs/components/side-nav/side-nav.test.ts
+++ b/docs/components/side-nav/side-nav.test.ts
@@ -89,7 +89,7 @@ describe('Components/Side Nav', () => {
     nav.setAttribute('route', ROUTE);
     nav.setAttribute('heading', HEADING);
 
-    expectedDocsContent = GRAPH.find((page) => page.route === ROUTE);
+    expectedDocsContent = GRAPH.find((page) => page.route === ROUTE) as DocsPage;
 
     document.body.appendChild(nav);
 
@@ -101,7 +101,7 @@ describe('Components/Side Nav', () => {
     let fullMenu: HTMLElement;
 
     beforeEach(async () => {
-      fullMenu = nav.querySelector('#main-menu');
+      fullMenu = nav.querySelector('#main-menu') as HTMLElement;
     });
 
     it('should not be null', () => {
@@ -118,18 +118,21 @@ describe('Components/Side Nav', () => {
     it('should have the expected number of section heading links', () => {
       const links = fullMenu.querySelectorAll('ul li a');
 
-      expect(links.length).to.equal(expectedDocsContent.data.tableOfContents.length);
+      expect(links.length).to.equal(expectedDocsContent.data?.tableOfContents?.length);
     });
 
     it('should have the expected content for section headings links', () => {
       const links = fullMenu.querySelectorAll('ul li a');
 
       links.forEach((link, index) => {
-        expect(link.textContent).to.equal(expectedDocsContent.data.tableOfContents[index].content);
+        expect(link.textContent).to.equal(
+          expectedDocsContent.data?.tableOfContents?.[index]?.content,
+        );
       });
     });
 
     afterAll(() => {
+      // @ts-expect-error
       fullMenu = null;
     });
   });
@@ -139,7 +142,7 @@ describe('Components/Side Nav', () => {
     let popoverSelector = 'compact-menu';
 
     beforeEach(async () => {
-      compactMenu = nav.querySelector(`#mobile-menu`);
+      compactMenu = nav.querySelector(`#mobile-menu`) as HTMLElement;
     });
 
     it('should not be null', () => {
@@ -179,24 +182,28 @@ describe('Components/Side Nav', () => {
     it('should have the expected number of section heading links', () => {
       const links = compactMenu.querySelectorAll('ul li a');
 
-      expect(links.length).to.equal(expectedDocsContent.data.tableOfContents.length);
+      expect(links.length).to.equal(expectedDocsContent.data?.tableOfContents?.length);
     });
 
     it('should have the expected content for section headings links', () => {
       const links = compactMenu.querySelectorAll('ul li a');
 
       links.forEach((link, index) => {
-        expect(link.textContent).to.equal(expectedDocsContent.data.tableOfContents[index].content);
+        expect(link.textContent).to.equal(
+          expectedDocsContent.data?.tableOfContents?.[index]?.content,
+        );
       });
     });
 
     afterEach(() => {
+      // @ts-expect-error
       compactMenu = null;
     });
   });
 
   afterEach(() => {
     nav.remove();
+    // @ts-expect-error
     nav = undefined;
   });
 
diff --git a/docs/components/side-nav/side-nav.tsx b/docs/components/side-nav/side-nav.tsx
index 109055ed..bbe240a6 100644
--- a/docs/components/side-nav/side-nav.tsx
+++ b/docs/components/side-nav/side-nav.tsx
@@ -14,14 +14,14 @@ export type DocsPage = Page & {
 };
 
 export default class SideNav extends HTMLElement {
-  route: string;
-  toc: TableOfContents;
-  heading: string;
+  route: string = '';
+  toc: TableOfContents = [];
+  heading: string = '';
 
   async connectedCallback() {
     const route = this.getAttribute('route') ?? '';
     const heading = this.getAttribute('heading') ?? '';
-    const page: DocsPage = (await getContent()).find((page) => page.route === route);
+    const page: DocsPage = (await getContent()).find((page) => page.route === route) as DocsPage;
 
     this.heading = heading;
     this.toc = page?.data?.tableOfContents ?? [];
diff --git a/docs/components/social-tray/social-tray.test.ts b/docs/components/social-tray/social-tray.test.ts
index 589d60bd..9a6f92d8 100644
--- a/docs/components/social-tray/social-tray.test.ts
+++ b/docs/components/social-tray/social-tray.test.ts
@@ -48,7 +48,7 @@ describe('Components/Social Tray', () => {
         const iconItem = ICONS.find((icon) => icon.title === link.getAttribute('title'));
 
         expect(iconItem).to.not.equal(undefined);
-        expect(link.getAttribute('href')).to.equal(iconItem.link);
+        expect(link.getAttribute('href')).to.equal(iconItem?.link);
         expect(link.getAttribute('target')).equal('_blank');
       });
     });
@@ -56,6 +56,7 @@ describe('Components/Social Tray', () => {
 
   afterEach(() => {
     tray.remove();
+    // @ts-expect-error
     tray = undefined;
   });
 });
diff --git a/package-lock.json b/package-lock.json
index 8717defe..344c321e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -55,7 +55,7 @@
         "remark-github": "^10.0.1",
         "stylelint": "^17.4.0",
         "stylelint-config-recommended": "^18.0.0",
-        "typescript": "^5.9.3",
+        "typescript": "^6.0.3",
         "typescript-eslint": "^8.46.2",
         "vite": "^7.3.1",
         "vitest": "^4.0.18"
@@ -13748,9 +13748,9 @@
       }
     },
     "node_modules/typescript": {
-      "version": "5.9.3",
-      "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.9.3.tgz",
-      "integrity": "sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw==",
+      "version": "6.0.3",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-6.0.3.tgz",
+      "integrity": "sha512-y2TvuxSZPDyQakkFRPZHKFm+KKVqIisdg9/CZwm9ftvKXLP8NRWj38/ODjNbr43SsoXqNuAisEf1GdCxqWcdBw==",
       "dev": true,
       "license": "Apache-2.0",
       "bin": {
diff --git a/package.json b/package.json
index f76d02b1..4a0a440a 100644
--- a/package.json
+++ b/package.json
@@ -103,7 +103,7 @@
     "remark-github": "^10.0.1",
     "stylelint": "^17.4.0",
     "stylelint-config-recommended": "^18.0.0",
-    "typescript": "^5.9.3",
+    "typescript": "^6.0.3",
     "typescript-eslint": "^8.46.2",
     "vite": "^7.3.1",
     "vitest": "^4.0.18"
diff --git a/src/jsx.d.ts b/src/jsx.d.ts
index 4c9286bb..ca6e96a5 100644
--- a/src/jsx.d.ts
+++ b/src/jsx.d.ts
@@ -9,13 +9,15 @@ type ElementAttributes<E extends HTMLElement> = {
   class?: string;
 };
 
+type PopoverState = 'auto' | 'manual' | 'hint';
 type PopoverTargetAction = 'show' | 'hide' | 'toggle';
-type PopoverTargetAttributes = {
+type PopoverAttributes = {
   // have to manage this manually, can't seem to get this from TypeScript itself (not sure if just skill issue? :D)
   // https://github.com/microsoft/TypeScript-DOM-lib-generator/issues/1790
   // it should be there per https://github.com/mdn/browser-compat-data/pull/21875
   // https://github.com/ProjectEvergreen/wcc/issues/236
   // per the spec, this should only apply to <button> and <input> elements.
+  popover?: PopoverState;
   popovertarget?: string;
   popovertargetaction?: PopoverTargetAction;
 };
@@ -23,7 +25,7 @@ type PopoverTargetAttributes = {
 // map each HTML tag to its attributes
 type IntrinsicElementsFromDom = {
   [E in keyof HTMLElementTagNameMap]: ElementAttributes<HTMLElementTagNameMap[E]> &
-    (E extends 'button' | 'input' ? PopoverTargetAttributes : {});
+    (E extends 'button' | 'input' ? PopoverAttributes : {});
 };
 
 declare namespace JSX {
diff --git a/test/cases/tsx-shadow-dom/src/heading.tsx b/test/cases/tsx-shadow-dom/src/heading.tsx
index 6d912ecc..9c1f45a5 100644
--- a/test/cases/tsx-shadow-dom/src/heading.tsx
+++ b/test/cases/tsx-shadow-dom/src/heading.tsx
@@ -1,5 +1,5 @@
 export default class HeadingComponent extends HTMLElement {
-  greeting: string;
+  greeting: string = '';
 
   sayHello() {
     alert(`Hello, ${this.greeting}!`);
diff --git a/test/cases/tsx/src/counter.tsx b/test/cases/tsx/src/counter.tsx
index 372eca3f..b1276802 100644
--- a/test/cases/tsx/src/counter.tsx
+++ b/test/cases/tsx/src/counter.tsx
@@ -29,14 +29,14 @@ export default class Counter extends HTMLElement {
       <div>
         <wcc-badge count={count}></wcc-badge>
         <h3 data-test="hello123">Counter JSX</h3>
+
         <button id="evt-this" onclick={this.decrement}>
           {' '}
           - (function reference)
         </button>
-        <button id="evt-assignment" onclick={(this.count -= 1)}>
-          {' '}
-          - (inline state update)
-        </button>
+        {/* TODO: https://github.com/ProjectEvergreen/wcc/issues/88 */}
+        {/* @ts-expect-error - onclick should be.a function, but we coerce to an assignment */}
+        <button id="evt-assignment" onclick={(this.count -= 1)}>{' '} - (inline state update)</button>
         <span>
           You have clicked{' '}
           <span class="red" id="expression">
@@ -44,6 +44,8 @@ export default class Counter extends HTMLElement {
           </span>{' '}
           times
         </span>
+        {/* TODO: https://github.com/ProjectEvergreen/wcc/issues/88 */}
+        {/* @ts-expect-error - onclick should be.a function, but we coerce to an assignment */}
         <button onclick={(this.count += 1)}> + (inline state update)</button>
         <button onclick={this.increment}> + (function reference)</button>
       </div>
diff --git a/test/cases/tsx/src/header.tsx b/test/cases/tsx/src/header.tsx
index 4149a5a4..e69e21bb 100644
--- a/test/cases/tsx/src/header.tsx
+++ b/test/cases/tsx/src/header.tsx
@@ -7,6 +7,11 @@ export default class Header extends HTMLElement {
           Close
         </button>
 
+        {/* @ts-expect-error popovertargetaction should only be valid if its one of the supported values */}
+        <button popovertarget="mobile-menu" popovertargetaction="wcc">
+          Close
+        </button>
+
         {/* @ts-expect-error popovertarget should only be valid on <button> and <input> */}
         <span popovertarget="mobile-menu">Close</span>
       </header>
diff --git a/vitest.config.ts b/vitest.config.ts
index 627823d0..d7f3eff8 100644
--- a/vitest.config.ts
+++ b/vitest.config.ts
@@ -43,7 +43,7 @@ function transformConstructableStylesheetsPlugin(): Plugin {
   return {
     name: 'transform-constructable-stylesheets',
     enforce: 'pre',
-    resolveId: (id, importer) => {
+    resolveId: (id, importer = '') => {
       if (
         // you'll need to configure this `importer` line to the location of your own components
         importer?.indexOf('/docs/components/') >= 0 &&
@@ -79,10 +79,10 @@ function transformRawImports(): Plugin {
     name: 'transform-raw-imports',
     enforce: 'pre',
     transform: async (src, id) => {
-      if (id.endsWith('?type=raw')) {
+      if (id.endsWith('?type=raw') && rawResource.intercept) {
         const url = new URL(`file://${id}`);
         const contents = await fs.readFile(url, 'utf-8');
-        const response = await rawResource.intercept(url, null, new Response(contents));
+        const response = await rawResource.intercept(url, new Request(url), new Response(contents));
         const body = await response.text();
 
         return {