Yes, I tested the network activity with the Chrome Development Tools and found nothing.
The only thing I found with an error in the console is the following:
Refused to load the font 'data:application/font-woff2;base64,d09GMgABAAAAAQ5sABIAAAADuOQAAQ4EAAEAgwAA...NRmDOWEh6diOI6NZmGl87N9J+r2JfpW2+5NhV/fGHLO57Yavbq7zaCewa/RDxp/aSH+luOPwAA' because it violates the following Content Security Policy directive: "default-src 'self' ". Note that 'font-src' was not explicitly set, so 'default-src' is used as a fallback.
I don't know if this will be.
What I could see, is that this error does not come out in Microsft Edge, and with that browser I can access to phpMyAdmin.
I don't know if it will be that, but in Chrome I get that error in the console, and in Edge not.
In Chrome I can't access and in Edge yes.