Function prepareForAction

source code/utils/computerUse/executor.ts:304–342

(
      allowlistBundleIds: string[],
      displayId?: number,
    )

    // ── Pre-action sequence (hide + defocus) ────────────────────────────

    async prepareForAction(
      allowlistBundleIds: string[],
      displayId?: number,
    ): Promise<string[]> {
      if (!getHideBeforeActionEnabled()) {
        return []
      }
      // prepareDisplay isn't @MainActor (plain Task{}), but its .hide() calls
      // trigger window-manager events that queue on CFRunLoop. Without the
      // pump, those pile up during Swift's ~1s of usleeps and flush all at
      // once when the next pumped call runs — visible window flashing.
      // Electron drains CFRunLoop continuously so Cowork doesn't see this.
      // Worst-case 100ms + 5×200ms safety-net ≈ 1.1s, well under the 30s
      // drainRunLoop ceiling.
      //
      // "Continue with action execution even if switching fails" — the
      // frontmost gate in toolCalls.ts catches any actual unsafe state.
      return drainRunLoop(async () => {
        try {
          const result = await cu.apps.prepareDisplay(
            allowlistBundleIds,
            surrogateHost,
            displayId,
          )
          if (result.activated) {
            logForDebugging(
              `[computer-use] prepareForAction: activated ${result.activated}`,
            )
          }
          return result.hidden
        } catch (err) {
          logForDebugging(
            `[computer-use] prepareForAction failed; continuing to action: ${errorMessage(err)}`,
            { level: 'warn' },
          )
          return []
        }
      })
    },

    async previewHideSet(
      allowlistBundleIds: string[],