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以下のコードをCApp_crossdomain.class.phpにいれれば解決すると思うのだが、
実際、Chromeがblockをし始めてからもう一度テストしたほうがいい。
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function setcookie_ex( $key, $val, $t, $url ) {
	//_alog($key."=".$val." ".$t." ".$url);
	$b_https = (( isset($_SERVER["HTTPS"]) ) && ( $_SERVER["HTTPS"] == "on" ));
	if ( $b_https ) {
		$hx = array();
		$hx[] = $key."=".$val;
		$hx[] = "path=".$url;
		$hx[] = "Max-Age=".($t-time());
		$hx[] = "SameSite=None";
		$hx[] = "Secure";
		$str = "Set-Cookie: ".implode("; ",$hx);
		//_alog($str);
		header($str);
	} else {
		setcookie( $key, $val, $t, $url );
	}
}


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A cookie associated with a cross-site resource at http://php7ub16.solar.lan/ was set without the `SameSite` attribute. A future release of Chrome will only deliver cookies with cross-site requests if they are set with `SameSite=None` and `Secure`. You can review cookies in developer tools under Application>Storage>Cookies and see more details at https://www.chromestatus.com/feature/5088147346030592 and https://www.chromestatus.com/feature/5633521622188032.
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https://stackoverflow.com/questions/58270663/samesite-warning-chrome-77
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This console warning is not an error or an actual problem — Chrome is just spreading the word about this new standard to increase developer adoption.

Release date for a fix is February 4, 2020 per: https://www.chromium.org/updates/same-site

I solved same problem by adding in response header

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response.setHeader("Set-Cookie", "HttpOnly;Secure;SameSite=Strict");
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SameSite prevents the browser from sending the cookie along with cross-site requests. The main goal is mitigating the risk of cross-origin information leakage. It also provides some protection against cross-site request forgery attacks. Possible values for the flag are Lax or Strict.

SameSite cookies explained here

Please refer this before applying any option.

Hope this helps you.
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https://stackoverflow.com/questions/39750906/php-setcookie-samesite-strict
header("Set-Cookie: key=value; path=/; domain=example.org; HttpOnly; SameSite=Lax");
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