How to host atypical TLDs on WHMCS / other places?
I had a new idea for a personal site I wanted to make. Nothing fancy, just a fun side project. So I do the usual, poke around with domain names until I find one available that fits the theme. Found one without too much difficulty! Bought it, cool.
But now, I login to one of the hosts I have used before and start to order some new shared hosting services, but lo and behold:

Now, I presume I could just toss some other domain in there, continue with registration, then set the real one up in the config area. But as someone who is still fairly noobish in this field, doing so makes me worry I'd run into other similar issues in other places (like in cPanel, or in WordPress, which I was probably going to use for this). The specific host I tried isn't important, butI tried 3 total, (granted, all ones with WHMCS), and I doubt the specific TLD would be a concern either, as it's one available at PorkBun and NameCheap (but not yet at CloudFlare) so hypothetically is not all that obscure.
Suggestions, alternative ideas, or thoughts appreciated!

Comments
What you’re running into is almost certainly a validation / support lag issue, not a problem with your domain or anything you did wrong.
What’s actually happening is that most shared hosts that use WHMCS rely on:
If your TLD is:
thæn WHMCS will reject it with “The domain you entered is not valid”, even though the domain is 100% real, registered, and working.
This is very common with:
You mentioned all 3 hosts use WHMCS, that’s the key detail.
Many hosts:
So you’re seeing the same underlying limitation, not three independent problems.
As for your question of using a “placeholder domain”, yes, this is normal and safe, and you won’t break anything if you do it correctly.
Typical approaches include using a temporary domain like:
Complete hosting signup
Add your real domain later via:
WordPress, cPanel, SSL, etc. do not care what domain you initially signed up with, as long as:
WordPress only stores:
If you want a cleaner alternatives (if you want to avoid hacks)
Option 1: Ask the host
Open a ticket and say:
“My domain is valid but your order form rejects the TLD. Can you add it or manually provision the account?”
Good hosts will fix it in minutes.
Option 2: Choose a host that doesn’t care
Some hosts:
Let you sign up with any domain
Or give you a temporary hostname by default
Option 3: Use Cloudflare later
Even if Cloudflare doesn’t support the TLD yet:
You can run DNS at your registrar
Move to Cloudflare later once supported
TL;DR
^ Original post cleaned up and formatted with AI
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I feel I do not completely understand your question, so will just add my 2 cents:
For a (very) long while I used the same domain as the primary / main / whatever_it's_called one with multiple cPanel shared hosts.
Then also added it to at least one (or two?) DirectAdmin host. The domain wasn't actually delegated all that time (no NS set).
Then I dropped that domain altogether - .INFO, which became unreasonably expensive. I keep using at least some of the providers mentioned above.
Just in case, all the plans I bought support more than one add-on domain. Unsure what will happen if only one domain is supported. That's probably a support ticket.
So I believe using something random or another domain you own shouldn't be an issue. You will just see it from time to time here and there.
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