Fatal error: Uncaught Error: Call to undefined function astra_get_tablet_breakpo

Suddenly wehn visiting our web site (as normal user) it displays

Fatal error: Uncaught Error: Call to undefined function astra_get_tablet_breakpoint() in /homepages/2/d784630739/htdocs/wpcms/wp-content/plugins/astra-addon/addons/colors-and-background/classes/dynamic-css/header-sections-dynamic.css.php:629 Stack trace: #0 /homepages/2/d784630739/htdocs/wpcms/wp-includes/class-wp-hook.php(287): astra_ext_header_sections_colors_dynamic_css(‘#content:before…’) #1 /homepages/2/d784630739/htdocs/wpcms/wp-includes/plugin.php(206): WP_Hook->apply_filters(‘#content:before…’, Array) #2 /homepages/2/d784630739/htdocs/wpcms/wp-content/plugins/astra-addon/classes/cache/class-astra-addon-cache.php(81): apply_filters(‘astra_dynamic_c…’, ”) #3 /homepages/2/d784630739/htdocs/wpcms/wp-content/plugins/astra-addon/classes/cache/class-astra-cache-base.php(358): Astra_Addon_Cache->get_dynamic_css() #4 /homepages/2/d784630739/htdocs/wpcms/wp-content/plugins/astra-addon/classes/cache/class-astra-addon-cache.php(108): Astra_Cache_Base->enqueue_styles(‘addon’) #5 /homepages/2/d784630739/htdocs/wpcms/wp-i in /homepages/2/d784630739/htdocs/wpcms/wp-content/plugins/astra-addon/addons/colors-and-background/classes/dynamic-css/header-sections-dynamic.css.php on line 629

and no contens is displayed. – The web site is dead.

Disanbleing the “Fixed header” Astra option fixes this, the website is showing bjut there is no menu baar at all in Desktop view (on mobile the mobile menu is shwoing).
As admin, when goging to customizer – header, the same error message is shown (always).

We use wordpress V 5.5.3 Astra V 2.3.1

BR – Jochen Klein

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