I found the easiest (and best) way to determine if the ExpressionEngine website is working to check the cookies set by the website.
By default, installing ExpressionEngine from the finished version calls its cookies with the exp_ prefix:

Naturally, these cookie settings ( cookie domain, cookie path and cookie prefix) can be canceled in the control panel, but many people never worry to change it by default.
If there are, the prefix will be different, but the rest of the cookie name will remain unchanged.
For example, compare the following two cookies:
exp_last_visit // Default EE Website cms__last_visit // Website for CampaignMonitor
You will notice that both cookies have a common last_visit (and so on for all cookie names).
You can test this newfound knowledge about these popular, high-speed ExpressionEngine:
Although there is no reliable way to determine which CMS can work on a site trying to guess the path of the system folder , asset names, common paths, and templates are time consuming and do not always point to the truth.
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