Problems since update to php 7.2
yesterday i changed our server to php 7.2. We are hosted by Strato.
Since then we have problems with some pages. Some needed plugins don't work anymore:
Slider Revolution, Force Regenerate Thumbnails, Layer Slider.
Also we got some errors.
On one hand, some pages are buggy and throw some errors:
See attached Picture Error Bottom Message
On the other hand there are errors when updating the web page:
See attached Picture Error Top Message

Comments
/mnt/web016/e0/94/57533094/htdocs/WordPress_SecureMode_01/wp-content/plugins/revslider/includes/framework/base-admin.class.php:71
#0
/mnt/web016/e0/94/57533094/htdocs/WordPress_SecureMode_01/wp-content/plugins/revslider/admin/revslider-admin.class.php(572):
RevSliderBaseAdmin::addMetaBox('Revolution Slid...', '', Array, NULL)
/mnt/web016/e0/94/57533094/htdocs/WordPress_SecureMode_01/wp-content/plugins/revslider/admin/revslider-admin.class.php(73):
RevSliderAdmin->addSliderMetaBox()
/mnt/web016/e0/94/57533094/htdocs/WordPress_SecureMode_01/wp-content/plugins/revslider/admin/revslider-admin.class.php(44):
RevSliderAdmin->init()
/mnt/web016/e0/94/57533094/htdocs/WordPress_SecureMode_01/wp-content/plugins/revslider/revslider.php(162):
RevSliderAdmin->__construct('/mnt/web016/e0/...')
/mnt/web016/e0/94/57533094/htdocs/WordPress_SecureMode_01/wp-admin/includes/plugin.php(567):
include_once('/mnt/web016/e0/...')
/mnt/web016/e0/94/57533094/htdocs/WordPress_SecureMode_01/wp-content/plugins/revslider/includes/framework/base-admin.class.php
on line 71
Here is an instruction on how to update the theme:
http://themes.muffingroup.com/betheme/documentation/#general
Theme updates will not delete your content unless you have changed the files directly in which case we suggest using a child theme.
We also recommend creating a backup file.
Please remove the theme completely from your theme folder and install a fresh copy. Do not overwrite files.
thanks