My workaround is to ban long press gesture for WKWebview until Apple fix it.
if (IOS14_OR_LATER) {
NSString *noneSelectString = @"document.documentElement.style.webkitTouchCallout='none';document.documentElement.style.webkitUserSelect='none';";
WKUserScript *noneSelectScript = [[WKUserScript alloc] initWithSource:noneSelectString injectionTime:WKUserScriptInjectionTimeAtDocumentEnd forMainFrameOnly:true];
[wkConfig.userContentController addUserScript:noneSelectScript];
}