Safari and browsers based on the Chromium codebase have removed options to disable the "ping" attribute, which allows site owners to track clicks on links from their pages. In the case of following a link with the "ping=URL" attribute in the "a href" tag, the browser additionally generates a POST request to the URL specified in the attribute, passing information about the transition through the HTTP_PING_TO header.
On the one hand, the "ping" attribute leads to the leakage of information about the user's actions on the page, which can be perceived as a violation of confidentiality, since in the tooltip displayed when hovering over the link, the browser does not inform the user about the additional sending of information and the user does not view the page code cannot determine if the "ping" attribute is applied or not. On the other hand, instead of "ping" for conversion tracking, forwarding through a transit link or intercepting clicks by JavaScript handlers can be used with the same success, "ping" only simplifies the organization of conversion tracking. In addition, "ping" is mentioned in the specifications of the HTML5 standardization organization WHATWG.
Firefox supports the "ping" attribute but is disabled by default (browser.send_pings in about:config). In Chrome, up to and including release 73, the "ping" attribute was enabled, but it was possible to disable it through the "chrome://flags#disable-hyperlink-auditing" option. In current experimental releases of Chrome, this flag has been removed and the "ping" attribute has been moved to the category of non-disabled features. Safari 12.1 also removed the ability to disable "ping", which was previously available via the WebKit2HyperlinkAuditingEnabled option.
Source: opennet.ru