CBLoginForm appears twice on the same page with Joomla Version3.7 ？？

Hello,

I have a home menuwhich CBLoginForm module assigned to it.(front side)

Once logout from the site, try to access certain menu url which is restricted to the resistered user.
Then I have "Please login first" message and it redirect to CBLogin Form.
The redirect url used to be "DOMAIN/index.php/component/comprofiler/login" in joomla ver3.6.5 and it was fine.
But after I upgrade Joomla to ver3.7, the redirect url became "DOMAIN/index.php/component/comprofiler/login?Itemid=HOMEMENUITEMID",and I have two CBLogin Form on the page.

It seems, once redirect to "domain/index.php/component/comprofiler/login" then CBLogin Form shows,
and then home menu is called then assined CBLogin Form appears again.
It may be wrong, but I don't know how to solve this problem.

Is this Joomla issue or CB? or is my settings wrong?

I appreciate if there's any help.
Thank you.

The Joomla users component redirects do not currently add the Itemid. The login showing twice is likely just the login page it self and your login module in whatever module position you have it in. See the below regarding the Itemid bug, which will be fixed in a later CB build.

forge.joomlapolis.com/issues/6594

Thank you for your quick reply.

However I was not sure what I should do exactly.

From your answer "The Joomla users component redirects do not currently add the itemid.",
I think am not supposed to have itemid in my redirect url, but I have itemid in my url.

How did i do:
1.Logout from site.
2.Directly input the URL or call the URL from bookmark, where user need to be logged in.(other than home url).
3.Site redirects to home menu page (where CBLogin module is assinged) and "Please login first" message shows.
This is where I have two CBLogin form, and it used to be one before Joomla was updated to ver3.7.

When redirects, it seems the file below is called.

file: joomla\libraries\cms\application\site.php
89. $url = JRoute::_('index.php?option=com_users&view=login', false);
90.
91. $this->enqueueMessage(JText::_('JGLOBAL_YOU_MUST_LOGIN_FIRST'));
92. $this->redirect($url);

line 89 makes the URL "DOMAIN/index.php/component/comprofiler/login?Itemid=HOMEMENUITEMID" and has itemid.
And at line 92 redirect to the url then I have two CBLogin form.

So I thought JRoute making wrong url at first but I was not sure how Joomla works well so it might be a CB problem...
I didn't change any settings or code, I just updated Joomla then this problem ocuured.

May be I should just wait for the bug to be fixed then this will be solved?
I am sorry If I didn't understanding your answer well.

You can try using Joomlas redirect component to redirect that exact URL to whatever URL you want. Aside from that you'll have to wait for the fix as again those redirects do not set the Itemid currently so it'll just use whatever Itemid is already in the URL, which in your case is the home page Itemid.

3.Site redirects to home menu page (where CBLogin module is assinged) and "Please login first" message shows.
This is where I have two CBLogin form, and it used to be one before Joomla was updated to ver3.7.

You're on CBs login page, not your home page. Then you've the login module either present on the Itemid in the URL or on all pages. Thus you've what appears to be 2 login forms. This is normal and perfectly fine.

Thank you. You're right. I was on CBs login page when redirects, sorry.

I understand that I am on CBs Login Page and I have login module on itemid in the URL,
thus there's two login forms.

So if I didn't have itemid in the redirect URL like below, I wouldn't have two login form ?
DOMAIN/index.php/component/comprofiler/login

And another thing is that I didn't really undestand what the bug fix will do.
My undestanding is that, currently the itemid in the URL is my home menu id,
but after the bug fix the itemid will be CBs login page id, so it solves my problem.
Am I undestanding right?

I am sorry for not understanding well.

The bug fix is to properly add the Itemid for the view to the URL. So if it redirects to CBs login page it'll properly add CBs login page Itemid so the URL has proper SEO. That's the only issue present here. The rest of the behavior you're seeing is entirely normal.