Fix remote File Explorer opening files via local fs:readFile

src/renderer/src/components/right-sidebar/FileExplorer.tsx

@@ -479,6 +479,7 @@ function FileExplorerFiles(): React.JSX.Element {
   }, [])
   const { handleClick, handleDoubleClick, handleWheelCapture } = useFileExplorerHandlers({
     activeWorktreeId,
+    runtimeEnvironmentId: activeRuntimeEnvironmentId,
     openFile,
     makePreviewFilePermanent,
     toggleDir: hasNameFilter ? handleToggleNameFilterDir : toggleDir,

src/renderer/src/components/right-sidebar/file-explorer-drag-scroll-marker.test.tsx

@@ -112,6 +112,7 @@ let capturedHandlers: ReturnType<typeof useFileExplorerHandlers> | null = null
 function HandlersProbe({ scrollRef }: { scrollRef: React.RefObject<HTMLDivElement | null> }): null {
   capturedHandlers = useFileExplorerHandlers({
     activeWorktreeId: 'wt-1',
+    runtimeEnvironmentId: null,
     openFile: vi.fn(),
     makePreviewFilePermanent: vi.fn(),
     toggleDir: vi.fn(),

src/renderer/src/components/right-sidebar/useFileExplorerHandlers.test.ts

@@ -72,6 +72,7 @@ describe('activateFileExplorerNode', () => {
     await activateFileExplorerNode({
       node: symlinkNode,
       activeWorktreeId: 'wt-1',
+      runtimeEnvironmentId: 'runtime-env-1',
       openFile,
       toggleDir: vi.fn(),
       loadDir: vi.fn(),
@@ -85,10 +86,42 @@ describe('activateFileExplorerNode', () => {
         filePath: '/repo/linked-docs',
         relativePath: 'linked-docs',
         worktreeId: 'wt-1',
+        runtimeEnvironmentId: 'runtime-env-1',
         language: expect.any(String),
         mode: 'edit'
       },
-      { preview: true }
+      { preview: true, suppressActiveRuntimeFallback: false }
+    )
+  })
+
+  it('opens local files without runtime fallback when no runtime owner is set', async () => {
+    const fileNode: TreeNode = {
+      name: 'README.md',
+      path: '/repo/README.md',
+      relativePath: 'README.md',
+      isDirectory: false,
+      depth: 0
+    }
+    const openFile = vi.fn()
+
+    await activateFileExplorerNode({
+      node: fileNode,
+      activeWorktreeId: 'wt-1',
+      runtimeEnvironmentId: null,
+      openFile,
+      toggleDir: vi.fn(),
+      loadDir: vi.fn(),
+      statPath: vi.fn(),
+      markPathAsDirectory: vi.fn(),
+      setSelectedPath: vi.fn()
+    })
+
+    expect(openFile).toHaveBeenCalledWith(
+      expect.objectContaining({
+        filePath: '/repo/README.md',
+        runtimeEnvironmentId: undefined
+      }),
+      { preview: true, suppressActiveRuntimeFallback: true }
     )
   })
 })

src/renderer/src/components/right-sidebar/useFileExplorerHandlers.ts

@@ -9,15 +9,17 @@ import { translate } from '@/i18n/i18n'
 
 type UseFileExplorerHandlersParams = {
   activeWorktreeId: string | null
+  runtimeEnvironmentId?: string | null
   openFile: (
     params: {
       filePath: string
       relativePath: string
       worktreeId: string
       language: string
       mode: 'edit'
+      runtimeEnvironmentId?: string | null
     },
-    options?: { preview?: boolean }
+    options?: { preview?: boolean; suppressActiveRuntimeFallback?: boolean }
   ) => void
   makePreviewFilePermanent: (filePath: string) => void
   toggleDir: (worktreeId: string, dirPath: string) => void
@@ -45,6 +47,7 @@ type OpenFileOptions = Parameters<UseFileExplorerHandlersParams['openFile']>[1]
 export async function activateFileExplorerNode(args: {
   node: TreeNode
   activeWorktreeId: string | null
+  runtimeEnvironmentId?: string | null
   openFile: (params: OpenFileParams, options?: OpenFileOptions) => void
   toggleDir: (worktreeId: string, dirPath: string) => void
   canToggleDirectories?: boolean
@@ -56,6 +59,7 @@ export async function activateFileExplorerNode(args: {
   const {
     node,
     activeWorktreeId,
+    runtimeEnvironmentId,
     openFile,
     toggleDir,
     canToggleDirectories = true,
@@ -116,15 +120,22 @@ export async function activateFileExplorerNode(args: {
       filePath: node.path,
       relativePath: node.relativePath,
       worktreeId: activeWorktreeId,
+      runtimeEnvironmentId: runtimeEnvironmentId ?? undefined,
       language: detectLanguage(node.name),
       mode: 'edit'
     },
-    { preview: true }
+    {
+      preview: true,
+      // Why: explicit local opens must not inherit the active runtime, so we
+      // encode "no runtime owner" via the fallback-suppression option.
+      suppressActiveRuntimeFallback: runtimeEnvironmentId === null
+    }
   )
 }
 
 export function useFileExplorerHandlers({
   activeWorktreeId,
+  runtimeEnvironmentId,
   openFile,
   makePreviewFilePermanent,
   toggleDir,
@@ -140,6 +151,7 @@ export function useFileExplorerHandlers({
       void activateFileExplorerNode({
         node,
         activeWorktreeId,
+        runtimeEnvironmentId,
         openFile,
         toggleDir,
         canToggleDirectories,
@@ -151,6 +163,7 @@ export function useFileExplorerHandlers({
     },
     [
       activeWorktreeId,
+      runtimeEnvironmentId,
       canToggleDirectories,
       loadDir,
       markPathAsDirectory,

src/renderer/src/components/right-sidebar/useFileExplorerInlineInput.ts

@@ -158,13 +158,19 @@ export function useFileExplorerInlineInput({
             }
             await refreshDir(inlineInput.parentPath)
             if (inlineInput.type === 'file') {
-              openFile({
-                filePath: fullPath,
-                relativePath: worktreePath ? fullPath.slice(worktreePath.length + 1) : name,
-                worktreeId: activeWorktreeId,
-                language: detectLanguage(name),
-                mode: 'edit'
-              })
+              const runtimeEnvironmentId =
+                fileContext.settings.activeRuntimeEnvironmentId?.trim() || null
+              openFile(
+                {
+                  filePath: fullPath,
+                  relativePath: worktreePath ? fullPath.slice(worktreePath.length + 1) : name,
+                  worktreeId: activeWorktreeId,
+                  runtimeEnvironmentId: runtimeEnvironmentId ?? undefined,
+                  language: detectLanguage(name),
+                  mode: 'edit'
+                },
+                { suppressActiveRuntimeFallback: runtimeEnvironmentId === null }
+              )
             }
           } catch (err) {
             // Refresh the directory even on failure so the tree stays consistent