1.7.x-fpm image seems to use wrong base `php:8.4-fpm`

[matwey]

Hello,

I see that the fpm image is currently based on php:8.4-fpm:

roundcubemail-docker/fpm/Dockerfile

Line 1 in 0bf9876

FROM php:8.4-fpm AS root

While Roundcube 1.7.0 seems to use php 8.5 features such as array_last:
https://github.com/roundcube/roundcubemail/blob/26b96793cb301de448a8bd67956ae3cfc6c0ccc1/program/include/rcmail_output_html.php#L343

Currently, I see the following with 1.7.0-fpm roundcube docker image:

NOTICE: PHP message: PHP Fatal error:  Uncaught Error: Call to undefined function array_last() in /var/www/html/program/include/rcmail_output_html.php:343
172.18.0.1 -  20/May/2026:11:31:27 +0000 "GET /index.php" 500
Stack trace:
#0 /var/www/html/program/include/rcmail_output_html.php(298): rcmail_output_html->load_skin()
#1 /var/www/html/program/include/rcmail_output_html.php(112): rcmail_output_html->set_skin()
#2 /var/www/html/program/include/rcmail_output_html.php(81): rcmail_output_html->init()
#3 /var/www/html/program/include/rcmail.php(589): rcmail_output_html->__construct()
#4 /var/www/html/program/include/rcmail.php(147): rcmail->load_gui()
#5 /var/www/html/program/include/rcmail.php(89): rcmail->startup()
#6 /var/www/html/public_html/index.php(43): rcmail::get_instance()
#7 {main}
  thrown in /var/www/html/program/include/rcmail_output_html.php on line 343

[pabzm]

Roundcube has symfony/polyfill-php85 as dependency. Your error messages suggest that this dependency is not installed.

Do you use a volume for the application source code?

Can you check if symfony/polyfill-php85 is contained in composer.lock?