fix(web-components): make anchor position targets fixed positioned

change/@fluentui-web-components-e18c2da8-7501-43a1-9c2c-b66039afa7a0.json

@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "make anchor position target fixed position",
+  "packageName": "@fluentui/web-components",
+  "email": "machi@microsoft.com",
+  "dependentChangeType": "patch"
+}

packages/web-components/src/dialog/dialog.styles.ts

@@ -41,7 +41,6 @@ export const styles = css`
 
     :host([type='non-modal']) dialog {
       inset: 0;
-      position: fixed;
       z-index: 2;
       overflow: auto;
     }

packages/web-components/src/dropdown/dropdown.stories.ts

@@ -493,3 +493,85 @@ export const OverflowScroll: Story = {
   `),
   args: { ...Default.args },
 };
+
+export const InsideDialog: Story = {
+  render: renderComponent(html<StoryArgs<FluentDropdown>>`
+    <fluent-button @click="${story => story.dialog.show()}">Open dialog</fluent-button>
+    <fluent-dialog ${ref('dialog')} aria-label="Dropdown in a dialog">
+      <fluent-dialog-body>
+        <h3 slot="title">Dropdown in a dialog</h3>
+        ${storyTemplate}
+      </fluent-dialog-body>
+    </fluent-dialog>
+  `),
+  args: { ...Default.args },
+};
+
+export const InsideDialogWithScrollingContent: Story = {
+  render: renderComponent(html<StoryArgs<FluentDropdown>>`
+    <fluent-button @click="${story => story.dialog.show()}">Open dialog</fluent-button>
+    <fluent-dialog ${ref('dialog')} aria-label="Dropdown in a dialog with scrolling content">
+      <fluent-dialog-body style="max-block-size: 30vb;">
+        <h3 slot="title">Dropdown in a dialog</h3>
+        <p>
+          Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce nec lectus non lorem iaculis luctus. Proin ac
+          dolor eget enim commodo pretium. Duis ut nibh ac metus interdum finibus. Integer maximus ante a tincidunt
+          pretium. Aliquam erat volutpat. Sed nec ante vel lectus dignissim commodo id ut elit. Curabitur ullamcorper
+          sapien id mauris interdum, ac placerat mi malesuada. Duis aliquam, dolor eget facilisis mollis, ante leo
+          tincidunt quam, vel convallis ipsum turpis et turpis. Mauris fermentum neque nec tortor semper tempus. Integer
+          malesuada, nunc ac cursus facilisis, lectus mauris interdum erat, in vulputate risus velit in neque. Etiam
+          volutpat ante nec fringilla tempus. Quisque et lobortis dolor. Fusce sit amet odio sed ipsum fringilla auctor.
+          Suspendisse faucibus tellus in luctus hendrerit. Vestibulum euismod velit non laoreet feugiat. Nam sit amet
+          velit urna. Cras consectetur tempor sem, in suscipit sem ultrices id. Vivamus id felis fringilla, scelerisque
+          nulla non, aliquam leo. In pharetra mauris ut enim ullamcorper, id suscipit quam ullamcorper. Quisque
+          tincidunt, felis nec congue elementum, mauris est finibus ex, ut volutpat ante est nec est. Aliquam tempor,
+          turpis ac scelerisque dignissim, metus velit rutrum sem, eget efficitur mauris erat in metus. Vestibulum in
+          urna massa. Donec eleifend leo at dui convallis aliquet. Integer eleifend, velit ut consequat tempus, enim
+          elit ultricies diam, at congue enim enim id nunc. Nullam fringilla bibendum nulla, at lacinia sem bibendum
+          eget. Nunc posuere ipsum sed enim facilisis efficitur. Pellentesque id semper mi, a feugiat sem. Nunc
+          interdum, leo ut tincidunt consectetur, nunc mauris accumsan nulla, vel ultricies velit erat nec sapien.
+          Praesent eleifend ex at odio scelerisque cursus. Morbi eget tellus sed sapien scelerisque cursus at a ante.
+          Sed venenatis vehicula erat eu feugiat. Ut eu elit vitae urna tincidunt pulvinar nec at nunc. Vestibulum eget
+          tristique sapien. Sed egestas sapien vel ante viverra pharetra. Cras sit amet felis at nulla tincidunt euismod
+          vitae et justo. Duis nec rutrum lectus, nec lobortis quam. Pellentesque habitant morbi tristique senectus et
+          netus et malesuada fames ac turpis egestas. Sed ac ex condimentum, consectetur felis non, maximus odio. Sed
+          mattis arcu id justo fringilla, a tristique purus vestibulum. Nulla nec fringilla quam. Sed ac elit ac sem
+          posuere cursus nec vitae mauris. Suspendisse nec pulvinar risus. Sed a tincidunt elit, in gravida tortor.
+          Quisque sollicitudin lectus vel interdum tempor. Fusce dictum fermentum sem sed suscipit. Vivamus sollicitudin
+          ex turpis, sit amet consequat leo auctor at. Donec fermentum aliquet lectus, sit amet efficitur nibh
+          pellentesque et. Curabitur dapibus quam vitae lectus pellentesque, vitae varius massa facilisis. Quisque
+          consectetur eros a arcu cursus fringilla. Fusce efficitur auctor nibh, nec sollicitudin eros semper eget. Cras
+          a elit ut tortor semper volutpat eu vel nunc. Duis dapibus quam risus, ac tristique nisl aliquam eu. Curabitur
+          vel ipsum non nunc euismod fringilla vel a lorem. Curabitur viverra magna ac justo fringilla, eu vestibulum
+          purus finibus. Donec elementum volutpat libero, in tempus massa convallis vitae. Curabitur vitae mauris id
+          urna dictum pharetra. Nullam vehicula arcu arcu, vitae elementum enim tincidunt at. Duis eleifend, lorem a
+          efficitur facilisis, nulla dolor finibus orci, et ullamcorper orci ex ac purus. Aenean sem lectus, malesuada
+          id magna id, facilisis condimentum nibh. Cras tempor neque mi, sit amet suscipit libero consectetur non.
+          Nullam id eleifend mauris. Mauris iaculis lectus eu scelerisque efficitur. In id suscipit libero. Donec
+          condimentum, purus ac laoreet facilisis, risus lorem facilisis neque, id volutpat felis mi eget metus. Nulla
+          facilisi. Donec consequat tincidunt nunc sed elementum. Integer consectetur tristique orci, ut congue justo
+          pellentesque eu. Fusce faucibus iaculis mauris, eu lobortis orci egestas eget. Nullam nec arcu bibendum,
+          cursus diam ac, facilisis enim. Nulla facilisi. Curabitur lacinia odio mauris, a gravida nisi volutpat in.
+          Aliquam at maximus felis. Vestibulum convallis dignissim urna id gravida.
+        </p>
+        ${storyTemplate}
+      </fluent-dialog-body>
+    </fluent-dialog>
+  `),
+  args: { ...Default.args },
+};
+
+export const InsideNonModalDialog: Story = {
+  render: renderComponent(html<StoryArgs<FluentDropdown>>`
+    <div style="min-block-size: 20rem;">
+      <fluent-button @click="${story => story.dialog.show()}">Open dialog</fluent-button>
+      <fluent-dialog ${ref('dialog')} type="non-modal" aria-label="Dropdown in a non-modal dialog">
+        <fluent-dialog-body>
+          <h3 slot="title">Dropdown in a non-modal dialog</h3>
+          ${storyTemplate}
+        </fluent-dialog-body>
+      </fluent-dialog>
+    </div>
+  `),
+  args: { ...Default.args },
+};

packages/web-components/src/dropdown/dropdown.styles.ts

@@ -59,7 +59,6 @@ export const styles = css`
   ${display('inline-flex')}
 
   :host {
-    anchor-name: --dropdown-trigger;
     box-sizing: border-box;
     color: ${colorNeutralForeground1};
     cursor: pointer;

packages/web-components/src/listbox/listbox.styles.ts

@@ -27,7 +27,7 @@ export const styles = css`
     box-sizing: border-box;
     flex-direction: column;
     margin: 0;
-    min-width: 160px;
+    min-inline-size: 160px;
     padding: ${spacingHorizontalXS};
     row-gap: ${spacingHorizontalXXS};
     width: auto;
@@ -40,26 +40,20 @@ export const styles = css`
 
   @supports (anchor-name: --anchor) {
     :host([popover]) {
-      position: absolute;
-      margin-block-start: 0;
-      max-height: var(--listbox-max-height, calc(50vh - anchor-size(self-block)));
-      min-width: anchor-size(width);
-      position-anchor: --dropdown;
-      position-area: block-end span-inline-end;
-      position-try-fallbacks: flip-inline, flip-block, --flip-block, block-start;
-    }
-
-    @position-try --flip-block {
-      bottom: anchor(top);
-      top: unset;
+      position: fixed;
+      max-block-size: var(--listbox-max-height, calc(50vh - anchor-size(self-block)));
+      min-inline-size: anchor-size(inline);
+      inset-block-start: anchor(end);
+      inset-inline-start: anchor(start);
+      position-try-fallbacks: flip-block, flip-inline, flip-inline flip-block;
     }
   }
 
   @supports not (anchor-name: --anchor) {
     :host([popover]) {
       margin-block-start: var(--margin-offset, 0);
-      max-height: var(--listbox-max-height, 50vh);
-      position: fixed;
+      max-block-size: var(--listbox-max-height, 50vh);
+      position: absolute;
     }
 
     :host([popover]${flipBlockState}) {

packages/web-components/src/menu-item/menu-item.styles.ts

@@ -147,9 +147,11 @@ export const styles = css`
     ::slotted([popover]) {
       margin: 0;
       max-height: var(--menu-max-height, auto);
-      position: absolute;
+      position: fixed;
       position-anchor: --menu-trigger;
-      position-area: inline-end span-block-end;
+      inset: unset;
+      inset-block-start: anchor(start);
+      inset-inline-start: anchor(end);
       position-try-fallbacks: flip-inline, block-start, block-end;
       z-index: 1;
     }
@@ -158,10 +160,6 @@ export const styles = css`
       display: none;
     }
 
-    ::slotted([popover]:popover-open) {
-      inset: unset;
-    }
-
     /* Fallback for no anchor-positioning */
     @supports not (anchor-name: --menu-trigger) {
       ::slotted([popover]) {

packages/web-components/src/menu/menu.styles.ts

@@ -16,18 +16,17 @@ export const styles = css`
     margin: 0;
     max-height: var(--menu-max-height, auto);
     position-anchor: --menu-trigger;
-    position-area: block-end span-inline-end;
+    inset: unset;
+    inset-block-start: anchor(end);
+    inset-inline-start: anchor(start);
     position-try-fallbacks: flip-block;
-    position: absolute;
+    position: fixed;
     z-index: 1;
   }
 
   :host([split]) ::slotted([popover]) {
-    position-area: block-end span-inline-start;
-  }
-
-  ::slotted([popover]:popover-open) {
-    inset: unset;
+    inset-inline-start: auto;
+    inset-inline-end: anchor(end);
   }
 
   ::slotted([popover]:not(:popover-open)) {

packages/web-components/src/tablist/tablist.styles.ts

@@ -201,7 +201,7 @@ export const styles = css`
       content: '';
       inline-size: 100%;
       inset: auto auto anchor(end) anchor(center);
-      position: absolute;
+      position: fixed;
       position-anchor: --tab;
       transform: translateX(-50%);
       transition-property: inset-inline, width;

packages/web-components/src/tooltip/tooltip.styles.ts

@@ -49,7 +49,7 @@ export const styles = css`
     padding: 4px ${spacingHorizontalMNudge} 6px;
     position: absolute;
     position-area: var(--position-area);
-    position-try-options: var(--position-try-options);
+    position-try-fallbacks: var(--position-try-options);
     width: auto;
     z-index: 1;
   }

packages/web-components/src/tooltip/tooltip.ts

@@ -256,7 +256,7 @@ export class Tooltip extends FASTElement {
       #${this.id} {
         inset: unset;
         position-anchor: ${anchorName};
-        position: absolute;
+        position: fixed;
         ${directionCSS}
         ${alignmentCSS}
       }