System requirements
macOS 13 or later. Squirrel is not required for Input Source Lock or standard app rules.
View download status →First launch
Open Input Sources to lock the current input source, or open App Rules to choose an input source for each app. Input Method Manager must remain running for automatic switching.
App Rules
Choose an installed app and target input source, then enable Follow Apps, or select an input source in the target app and remember it from the menu bar. If a target is disabled or removed, its rule is kept and marked unavailable.
Squirrel configuration
The app first checks locally whether Squirrel is installed. Once detected, it accepts only the fixed ~/Library/Rime configuration folder. Access is used only for the Squirrel settings you choose to manage.
Save and apply
Changing a control updates only the preview. After you click “Save and Apply,” Input Method Manager checks conflicts, creates a backup, writes, and redeploys.
A change did not take effect
Open Deployment Diagnostics to review the save, redeployment, and verification record. Avoid repeatedly overwriting configuration files by hand.
Frequently asked questions
Do I have to install or authorize Squirrel?
No. Input Source Lock, standard app rules, menu bar controls, and the desktop input status bar work independently. Squirrel and folder access are needed only to set Squirrel's default Chinese or English mode or use other Squirrel configuration features.
What happens if Squirrel is not installed?
When you open Squirrel Settings, the app checks locally for Squirrel first. If Squirrel is missing, no folder-authorization panel is opened; the app asks you to install and launch Squirrel instead. Input Source Lock, App Rules, and other general management features remain available.
How do I reopen the main window after closing it?
Choose Open Main Window from the macOS Window menu (Command–0), or click the app in the Dock. The menu bar control also shows Open Main Window whenever the main window is closed.
Why cannot Input Source Lock and Follow Apps run together?
Both features can switch input sources automatically. Enabling either mode stops the other so they cannot interfere with each other.
Why did an app rule not switch the input source?
Make sure a rule exists, Follow Apps is enabled, the target input source remains enabled in macOS, and Input Method Manager is still running. Apps without a rule are left unchanged.
How do I remember the current app from the menu bar?
Switch to the target app, choose the input source you want it to use, open Input Method Manager's menu bar control, and click Remember. If a different rule already exists or Input Source Lock is active, the app asks for confirmation first.
Why does an app rule say its target is unavailable?
The input source may have been disabled, removed, or assigned a new system identifier after an update. The rule is kept; choose another currently enabled input source under App Rules.
Why can the input source still change while locked?
Make sure the app is still running and the target remains enabled in macOS. The app stops locking after repeated switch-back failures so it does not fight the system indefinitely.
Can I choose any configuration directory?
No. Input Method Manager automatically identifies the directory actually used by Squirrel for the current macOS user, preventing checks in one location and edits in another.
Can I restore a change?
Yes. Input Method Manager creates a complete configuration snapshot before saving. You can inspect and restore snapshots from Backup and Restore.
Will the preview look exactly like the real Squirrel window?
The preview is designed for comparing layout, font size, and spacing. Final rendering still depends on the current Squirrel and macOS versions, so small differences are possible.
Send feedback
Feedback is sent directly to the Input Method Manager support console. Enter a contact email and a description of the issue, up to 1,000 characters. Do not submit dictionaries, full configuration files, typed input, or other unnecessary personal information. Read the privacy policy.
Contact support
For privacy or product-support questions, email [email protected].