diff --git a/src/renderer/src/components/GitHubItemDialog.tsx b/src/renderer/src/components/GitHubItemDialog.tsx
index 360e272486e..7e636618d77 100644
--- a/src/renderer/src/components/GitHubItemDialog.tsx
+++ b/src/renderer/src/components/GitHubItemDialog.tsx
@@ -51,8 +51,6 @@ import { ButtonGroup } from '@/components/ui/button-group'
 import { Input } from '@/components/ui/input'
 import { useMountedRef } from '@/hooks/useMountedRef'
 import { useConfirmationDialog } from '@/components/confirmation-dialog'
-import { Sheet, SheetContent, SheetDescription, SheetTitle } from '@/components/ui/sheet'
-import { VisuallyHidden } from 'radix-ui'
 import {
   Accordion,
   AccordionContent,
@@ -186,8 +184,6 @@ import { PER_REPO_FETCH_LIMIT } from '../../../shared/work-items'
 import { translate } from '@/i18n/i18n'
 import { getSettingsForRepoRuntimeOwner } from '@/lib/repo-runtime-owner'
 
-const IS_MAC = navigator.userAgent.includes('Mac')
-
 // Why: the GH item dialog can be opened from any work-item list surface and
 // doesn't have the full owner/repo context the list's cache entry carries.
 // Parsing the canonical `https://github.com/{owner}/{repo}/...` URL is the
@@ -283,7 +279,6 @@ type GitHubItemDialogProps = {
   repoId?: string | null
   sourceContext?: TaskSourceContext | null
   initialTab?: ItemDialogTab
-  variant?: 'sheet' | 'page'
   backLabel?: string
   /** Called when the user clicks the primary CTA to start work from this item. */
   onUse: (item: GitHubWorkItem) => void
@@ -5695,7 +5690,6 @@ export default function GitHubItemDialog({
   repoId,
   sourceContext,
   initialTab,
-  variant = 'sheet',
   backLabel = 'Back',
   projectOrigin,
   onUse,
@@ -6161,7 +6155,7 @@ export default function GitHubItemDialog({
     [details?.pullRequestId, detailsCacheKey, repoPath, sourceContext, workItem]
   )
 
-  const isIssuePage = variant === 'page' && workItem?.type === 'issue'
+  const isIssuePage = workItem?.type === 'issue'
   const ownerRepo = workItem ? parseOwnerRepoFromItemUrl(workItem.url) : null
   const issueStateBadgeTone =
     localState === 'closed' ? 'bg-rose-600 text-white' : 'bg-emerald-600 text-white'
@@ -6367,19 +6361,17 @@ export default function GitHubItemDialog({
       ) : (
         <div className="flex-none border-b border-border/60 bg-card/80 px-4 py-3 shadow-xs backdrop-blur supports-[backdrop-filter]:bg-card/70">
           <div className="flex items-start gap-3">
-            {variant === 'page' ? (
-              <Button
-                type="button"
-                variant="ghost"
-                size="sm"
-                onClick={onClose}
-                className="-ml-1 mt-0.5 shrink-0 gap-1.5"
-                aria-label={backLabel}
-              >
-                <ChevronLeft className="size-4" />
-                {backLabel}
-              </Button>
-            ) : null}
+            <Button
+              type="button"
+              variant="ghost"
+              size="sm"
+              onClick={onClose}
+              className="-ml-1 mt-0.5 shrink-0 gap-1.5"
+              aria-label={backLabel}
+            >
+              <ChevronLeft className="size-4" />
+              {backLabel}
+            </Button>
             <div className="mt-0.5 flex size-8 shrink-0 items-center justify-center rounded-md border border-border/60 bg-muted/40 text-muted-foreground">
               <Icon className="size-4" />
             </div>
@@ -6488,26 +6480,6 @@ export default function GitHubItemDialog({
                   {translate('auto.components.GitHubItemDialog.3fdf777817', 'Open on GitHub')}
                 </TooltipContent>
               </Tooltip>
-              {variant === 'sheet' ? (
-                <Tooltip>
-                  <TooltipTrigger asChild>
-                    <Button
-                      variant="ghost"
-                      size="icon-sm"
-                      onClick={onClose}
-                      aria-label={translate(
-                        'auto.components.GitHubItemDialog.45af57999b',
-                        'Close preview'
-                      )}
-                    >
-                      <X className="size-4" />
-                    </Button>
-                  </TooltipTrigger>
-                  <TooltipContent side="bottom" sideOffset={6}>
-                    {translate('auto.components.GitHubItemDialog.474c59b4b3', 'Close · Esc')}
-                  </TooltipContent>
-                </Tooltip>
-              ) : null}
             </div>
           </div>
         </div>
@@ -6780,63 +6752,9 @@ export default function GitHubItemDialog({
     </div>
   ) : null
 
-  if (variant === 'page') {
-    return (
-      <div className="flex h-full min-h-0 flex-col overflow-hidden rounded-md border border-border/50 bg-background shadow-sm">
-        {content}
-      </div>
-    )
-  }
-
   return (
-    <Sheet open={workItem !== null} onOpenChange={(open) => !open && onClose()}>
-      <SheetContent
-        side="right"
-        showCloseButton={false}
-        className={cn(
-          'flex w-full flex-col gap-0 overflow-hidden p-0 lg:max-w-[var(--github-item-dialog-max-width)]',
-          // Why: native macOS traffic lights are drawn above web content, so a
-          // nearly full-width right sheet must leave the titlebar's 80px
-          // traffic-light pad uncovered instead of relying on z-index.
-          IS_MAC
-            ? 'max-w-[calc(100vw-(80px/var(--ui-zoom-factor,1)))] sm:max-w-[calc(100vw-(80px/var(--ui-zoom-factor,1)))]'
-            : 'max-w-[calc(100vw-1rem)] sm:max-w-[calc(100vw-1rem)]'
-        )}
-        style={
-          {
-            '--github-item-dialog-max-width': IS_MAC
-              ? 'min(calc(100vw - (80px / var(--ui-zoom-factor, 1))), 1600px)'
-              : 'min(calc(100vw - 2rem), 1600px)'
-          } as React.CSSProperties
-        }
-        onOpenAutoFocus={(event) => {
-          // Why: focusing the first actionable element inside the drawer
-          // causes the "Start workspace" action to receive focus and
-          // get visually highlighted on open. Preventing auto-focus keeps the
-          // drawer feeling like a passive preview until the user acts.
-          event.preventDefault()
-        }}
-      >
-        {/* Why: SheetTitle/Description are required by Radix Dialog for a11y,
-            but the visible header carries the same info. Wrap each with
-            `asChild` so the VisuallyHidden span wraps the element cleanly. */}
-        <VisuallyHidden.Root asChild>
-          <SheetTitle>
-            {workItem?.title ??
-              translate('auto.components.GitHubItemDialog.3853476a97', 'GitHub item')}
-          </SheetTitle>
-        </VisuallyHidden.Root>
-        <VisuallyHidden.Root asChild>
-          <SheetDescription>
-            {translate(
-              'auto.components.GitHubItemDialog.3ab6ac0fc8',
-              'Preview and edit the selected GitHub issue or pull request.'
-            )}
-          </SheetDescription>
-        </VisuallyHidden.Root>
-
-        {content}
-      </SheetContent>
-    </Sheet>
+    <div className="flex h-full min-h-0 flex-col overflow-hidden rounded-md border border-border/50 bg-background shadow-sm">
+      {content}
+    </div>
   )
 }
diff --git a/src/renderer/src/components/TaskPage.tsx b/src/renderer/src/components/TaskPage.tsx
index a52c55b3a0b..aa2749fce65 100644
--- a/src/renderer/src/components/TaskPage.tsx
+++ b/src/renderer/src/components/TaskPage.tsx
@@ -8586,7 +8586,7 @@ export default function TaskPage(): React.JSX.Element {
                 initialTab={dialogInitialTab}
                 repoPath={dialogRepoPath}
                 repoId={dialogWorkItem.repoId}
-                variant="page"
+                sourceContext={dialogSourceContext}
                 backLabel="GitHub list"
                 onUse={(item) => {
                   setDialogWorkItem(null)
@@ -12074,24 +12074,6 @@ export default function TaskPage(): React.JSX.Element {
         </DialogContent>
       </Dialog>
 
-      <GitHubItemDialog
-        workItem={dialogWorkItem}
-        repoPath={
-          // Why: the dialog is for a single item — resolve its repoPath from the
-          // item's own repoId (set when fan-out merged the list) so it works in
-          // cross-repo mode too. Reusing the memoized repo map avoids an O(n)
-          // scan on every render while the dialog is open.
-          dialogWorkItem ? (repoMap.get(dialogWorkItem.repoId)?.path ?? null) : null
-        }
-        repoId={dialogWorkItem?.repoId ?? null}
-        sourceContext={dialogSourceContext}
-        onUse={(item) => {
-          setDialogWorkItem(null)
-          handleUseWorkItem(item)
-        }}
-        onClose={() => setDialogWorkItem(null)}
-      />
-
       <GitLabItemDialog
         item={gitlabDialogItem}
         // Why: dialog's repoPath has to come from the clicked item's
diff --git a/src/renderer/src/components/github-item-dialog-source-boundary.test.ts b/src/renderer/src/components/github-item-dialog-source-boundary.test.ts
index 1e70364f09c..83c8b3cac47 100644
--- a/src/renderer/src/components/github-item-dialog-source-boundary.test.ts
+++ b/src/renderer/src/components/github-item-dialog-source-boundary.test.ts
@@ -17,6 +17,15 @@ function sourceBetween(source: string, startPattern: string, endPattern: string)
 }
 
 describe('GitHubItemDialog source host boundaries', () => {
+  it('does not keep the stale right-side sheet owner', () => {
+    const source = componentSource('GitHubItemDialog.tsx')
+
+    expect(source).not.toContain('@/components/ui/sheet')
+    expect(source).not.toContain('<Sheet')
+    expect(source).not.toContain('<SheetContent')
+    expect(source).not.toContain("variant?: 'sheet'")
+  })
+
   it('routes reviewer metadata and reviewer mutations through the task source context', () => {
     const source = componentSource('GitHubItemDialog.tsx')
     const section = sourceBetween(source, 'function PRReviewersPanel', 'function isPRFileViewed')
diff --git a/src/renderer/src/components/github-project/ProjectViewWrapper.tsx b/src/renderer/src/components/github-project/ProjectViewWrapper.tsx
index c46d8120aba..f76361d3654 100644
--- a/src/renderer/src/components/github-project/ProjectViewWrapper.tsx
+++ b/src/renderer/src/components/github-project/ProjectViewWrapper.tsx
@@ -793,6 +793,33 @@ export default function ProjectViewWrapper(_props: Props = {} as Props): React.J
             }
           }}
         />
+      ) : visibleTable && resolvedDialogRepoItem ? (
+        <GitHubItemDialog
+          workItem={resolvedDialogRepoItem.workItem}
+          repoPath={resolvedDialogRepoItem.repoPath}
+          repoId={resolvedDialogRepoItem.repoId}
+          projectOrigin={resolvedDialogRepoItem.origin}
+          backLabel={translate(
+            'auto.components.github.project.ProjectViewWrapper.1aa7c952b9',
+            'Project view'
+          )}
+          onUse={(item) => {
+            const current = resolvedDialogRepoItem
+            setDialogRepoItem(null)
+            void launchWorkItemDirect({
+              item,
+              repoId: current.workItem.repoId,
+              launchSource: 'task_page',
+              telemetrySource: 'sidebar',
+              openModalFallback: () => {
+                if (item.url) {
+                  void window.api.shell.openUrl(item.url)
+                }
+              }
+            })
+          }}
+          onClose={() => setDialogRepoItem(null)}
+        />
       ) : visibleTable ? (
         <ProjectViewList
           table={visibleTable}
@@ -811,36 +838,6 @@ export default function ProjectViewWrapper(_props: Props = {} as Props): React.J
         />
       ) : null}
 
-      {/* Full repo-backed dialog — writes still go through slug-addressed
-          mutation helpers (see design §Dialog editing from Project rows, line
-          707) so a row from another repo cannot accidentally edit the active
-          workspace. */}
-      <GitHubItemDialog
-        workItem={resolvedDialogRepoItem?.workItem ?? null}
-        repoPath={resolvedDialogRepoItem?.repoPath ?? null}
-        repoId={resolvedDialogRepoItem?.repoId ?? null}
-        projectOrigin={resolvedDialogRepoItem?.origin}
-        onUse={(item) => {
-          const current = resolvedDialogRepoItem
-          setDialogRepoItem(null)
-          if (!current) {
-            return
-          }
-          void launchWorkItemDirect({
-            item,
-            repoId: current.workItem.repoId,
-            launchSource: 'task_page',
-            telemetrySource: 'sidebar',
-            openModalFallback: () => {
-              if (item.url) {
-                void window.api.shell.openUrl(item.url)
-              }
-            }
-          })
-        }}
-        onClose={() => setDialogRepoItem(null)}
-      />
-
       {/* Slug-only simplified dialog for rows whose repo isn't added to Orca.
           Why: no Start-work affordance lives inside the slug dialog — the
           parent's `handleStartWork`/`repoNotInOrca` modal owns that flow, so
diff --git a/src/renderer/src/components/tab-bar/TabBar.windows-shell-launch.test.ts b/src/renderer/src/components/tab-bar/TabBar.windows-shell-launch.test.ts
index 343a22b5e7b..83d50f864fa 100644
--- a/src/renderer/src/components/tab-bar/TabBar.windows-shell-launch.test.ts
+++ b/src/renderer/src/components/tab-bar/TabBar.windows-shell-launch.test.ts
@@ -81,6 +81,7 @@ vi.mock('react', async () => {
   return {
     ...actual,
     memo: <T>(component: T) => component,
+    useCallback: <T extends (...args: never[]) => unknown>(callback: T) => callback,
     useEffect: () => {},
     useLayoutEffect: () => {},
     useCallback: <T extends (...args: never[]) => unknown>(callback: T) => callback,
diff --git a/src/renderer/src/components/task-page-source-switch-boundary.test.ts b/src/renderer/src/components/task-page-source-switch-boundary.test.ts
index 8207399c98b..b2dee55ce00 100644
--- a/src/renderer/src/components/task-page-source-switch-boundary.test.ts
+++ b/src/renderer/src/components/task-page-source-switch-boundary.test.ts
@@ -13,6 +13,23 @@ function sourceBetween(source: string, startPattern: string, endPattern: string)
 }
 
 describe('TaskPage source switching host boundary', () => {
+  it('renders GitHub item details from the task-detail page owner only', () => {
+    const detailSection = sourceBetween(
+      TASK_PAGE_SOURCE,
+      "{taskSource === 'github' && dialogWorkItem ?",
+      ") : taskSource === 'github' && githubMode === 'project' ?"
+    )
+    const modalSection = sourceBetween(
+      TASK_PAGE_SOURCE,
+      '<Dialog\n        open={newJiraIssueOpen}',
+      '<GitLabItemDialog'
+    )
+
+    expect(detailSection).toContain('<GitHubItemDialog')
+    expect(detailSection).toContain('sourceContext={dialogSourceContext}')
+    expect(modalSection).not.toContain('<GitHubItemDialog')
+  })
+
   it('switches task source without mutating the focused run host', () => {
     const section = sourceBetween(
       TASK_PAGE_SOURCE,