A while back there was some issue with the wildcard expansion generating excessively long URLs that would be rejected by the web server. Jeff imposed an expansion limit as a workaround, which seems to limit the wildcard matches to the top 20 most popular applicable tags.
To use LINE we have to download/install something, it can't used by typing/clicking a link, so it's off-topic here.
Questions about API's usually are off-topic here.
Because LINE is off-topic here, it doesn't make sense to have a tag for it so, there isn't a easy way to find posts that are about LINE.
Are API questions on topic or off topic?