You can submit a report here (opens new window). Note that we can't guarantee that we will reply to your message.
How do I report an issue about the LINE Platform?
How does auto login work?
Auto login can be used in these situations. You don't need to perform any special configurations when implementing LINE Login into your web app to use Auto login.
iOS
- Auto login can be used when accessing a web app where LINE Login v2.0 or v2.1 is implemented using LINE's in-app browser or the Safari browser.
Android
- Auto login can be used when accessing a web app where LINE Login v2.0 or v2.1 is implemented using LINE's in-app browser or external browsers such as Chrome.
Auto login isn't supported for devices other than iOS and Android devices, devices where LINE isn't installed, and in browsers other than the Safari browser for iOS.
Also, we use iOS's Universal links (opens new window) and Android's Common intents (opens new window) features to perform auto login on external browsers. Check the official documentation for each OS for information on concepts such as how the dialog is displayed when using these features, the OS requirements for using these features, and how to disable these features.
For more information, see Auto login in the LINE Login documentation.
About automatic login from the Yahoo! JAPAN app
Auto login is enabled when accessing a web app that incorporates LINE Login with PKCE implementation from the Yahoo! Japan app. For more information on PKCE support for LINE Login, see PKCE support for LINE Login in the LINE Login documentation.
Is it possible for the user IDs of users who have deleted their LINE accounts to be used again?
About the user ID issued by a certain provider, in the case that the corresponding LINE account is deleted, the same user ID won't be reused for other LINE accounts within the provider.
For more information on user IDs, see What are the user ID, group ID, room ID, and one-on-one chat ID values?
LINE Login shows the "Log in with the following account" screen. Does this mean that auto login has failed?
No. Single Sign On (SSO) login is running instead of auto login. For more information, see Single Sign On (SSO) Login.
Once a user ID is issued, can it be changed at any time?
User IDs are issued by each channel provider. Once a user ID (userId) is issued for a specific provider, it won't change unless the user deletes their LINE account.
The user ID won't change even if the user transfers their LINE account to another device.
If a user deletes their LINE account and then re-creates a LINE account with the same phone number, the user ID will change.
For more information on user IDs, see What are the user ID, group ID, room ID, and one-on-one chat ID values?
To restrict access from unauthorized parties when calling the Webhook URL, can you publish the IP address of LINE Corporation?
We don't disclose IP addresses.
We prevent unauthorized requests through SSL communication and Verifying signatures included in the webhook.
What are the user ID, group ID, room ID, and one-on-one chat ID values?
The user ID used by the LINE Platform identifies a user and has the following characteristics:
The value is generated by the LINE Platform, not by a user. This is different from the LINE ID on LINE used to search for friends.
Different user IDs are generated based on the provider of the channel. As long as channels have the same provider, regardless of whether the channel is for LINE Login or Messaging API, the same user ID is used for the users of the channels.
The user ID value is a string that matches the regular expression,
U[0-9a-f]{32}.
The group ID and room ID used for group chats are values generated by the LINE Platform to identify groups and rooms.
The group ID is a string that matches the regular expression, C[0-9a-f]{32}, and the room ID is a string that matches the regular expression, R[0-9a-f]{32}.
In a LINE Front-end Framework (LIFF) app, the one-on-one chat ID (utou ID) is used to identify a one-on-one chat in addition to the three types of IDs mentioned above.
The one-on-one chat ID value is a string that matches the regular expression, UU[0-9a-f]{130}.
When sending a text message, a series of numbers may be considered a phone number, or a string of characters may be considered a URL, and be linked as such. What causes this behavior?
The behavior depends on the specifications of the OS, such as Android or iOS.
This isn't controlled by the LINE app.
Where can I check the status of LINE API outage?
You can check the current status of a LINE API outage using these methods:
- Outage report in the news section of the LINE Developers site
- LINE API Status (opens new window)
Which browsers does LINE Developers support?
The supported browsers are Google Chrome, Safari, and Microsoft Edge.
Internet Explorer isn't supported.