I ran into a weird issue with TinyMCE:

I added this anchor to my content:

Code: Please login/register for access

…but TinyMCE removes Code: Please login/register for access automatically. Strangely, if I change the id to something like Code: Please login/register for access:

Code: Please login/register for access

it stays perfectly fine.

Why does this happen?

It turns out that Code: Please login/register for access is a reserved word in HTML and CSS. Browsers treat Code: Please login/register for access as a property (Code: Please login/register for access), and TinyMCE’s cleanup routines try to prevent conflicts. Since your anchor is empty, TinyMCE thinks it might cause issues and removes it.

How to fix it: Avoid reserved words for ids - rename the anchor id to something like Code: Please login/register for access or Code: Please login/register for access, or Code: Please login/register for access like I did.

Summary:
TinyMCE removes Code: Please login/register for access because Code: Please login/register for access is a reserved word. Using a different id prevents this.