IRC.com is Vendor-Locked (Freenode)
There are numerous Web clients for IRC, but the one in IRC.com says: "Ready to connect • Click Connect button to connect to IRC" (which IRC? What network?)
Well, they give only one option, 'Leenode':
We mentioned this in passing the other day.
What else is left to use?
"Mibbit has shut down":
Mibbit now recommends a Web client (Kiwi IRC) that does not properly work with 'other' networks (in embedded mode), even though it used to.
It should be noted that this Web client was financially supported (its development, maybe hosting too) by Lee of 'Leenode'.
There are a few other Web clients one can install on one's server (QuakeNet has one). We tried a few over the years. We didn't like them.
Thankfully, however, IRC does not rely on any Web clients. IRC predates the Web and it's best used as a native, standalone client, not something inside the Web browser. █