# FAQ entries tagged #LINE app

Q
When trying social login with google account in the LIFF browser or LINE's in-app browser, an error with a status code 403 and an error code disallowed_useragent will be displayed.

In the LIFF browser and LINE's in-app browser, the user's social login with google account isn't allowed. This is because Google's OAuth 2.0 Policies (opens new window) disallow authorization requests from WebView to Google.

Therefore, when the user tries social login with google account in the LIFF browser or LINE's in-app browser, an error with a status code 403 and an error code disallowed_useragent (opens new window) will be displayed.

Q
Why can't I open a page and an error message appears in the LIFF browser or LINE's in-app browser?

In the LIFF browser and LINE's in-app browser, if there is a problem with the SSL/TLS certificate on a network path, an error may occur and you may not be able to open the page. The following are examples of the error message that appears when the page doesn't open:

  • This connection isn't private
  • Unable to process your request due to a temporary error. Please try again.
  • An unknown error occurred. Please try again later.
  • Unable to open page. Server not found.
  • This site is potentially unsafe. Please close this screen.

Note that even if there is no problem with the certificate of an accessed page, you may receive an error message if there is a certificate problem when loading external resources contained on the page. For example, if you specify a path on a server with a certificate problem in the src attribute of a <script> element as shown below, you may receive an error message.

<script charset="utf-8" src="{A path on a server with a certificate problem}"></script>
Q
How are the URL previews in chats and on LINE VOOM generated?

LINE uses Open Graph Protocol tags from websites to generate URL previews.

The three OGP tags used by LINE:

# Open Graph Protocol tag Example
1 og:title <meta property="og:title" content="LINE : Free Calls & Messages">
2 og:description <meta property="og:description" content="LINE is a new communication app">
3 og:image <meta property="og:image" content="http://static.naver.jp/line_lp/img/ogp.png">

Example of URL preview:

URL preview in chat

OGP configuration

Even if you don't configure OGP tags, any text or image within the URL will be automatically retrieved to generate a URL preview.

For example, for the Title, if there is no available information in og:title, the text within the title tag will be displayed. Likewise, for the Summary, if there is no available information in og:description, the text within either the description tag or the body will be displayed (If there is no retrievable information, nothing will be displayed in the preview).

LINE uses only the three OGP tags listed above. URL previews will not include information contained in any other OGP tags.

Tip

A cache-deletion tool (opens new window) for deleting the LINE server side cache of your URL preview is now available.