CSS "..." false-positive for URL

[vampiricwulf]

Describe the bug
Added custom css:

#profile-info-text::before {
    content: "BIO_DATA_LOADED...";
    display: block;
    color: var(--pink);
    font-size: 10px;
    margin-bottom: 5px;
    text-shadow: 0 0 5px var(--pink);
}

Gave me the unsupported URL error (must use imgur, github, etc.).
Deleted the ... and it sync without error, so ... is improperly being read as a URL.

Browser
Watefox 6.6.6

OldTwitter version
v1.9.3