[Support request] "View general debug log file by clicking here." throws WordPress fatal error.

Clicking the view general debug log file link gets me an email from WordPress reporting a fatal error:

Error ————————–Details
An error of type E_ERROR was caused in line 39 of the file /home/fk7vwt4wp8j5/public_html/wp-content/plugins/simple­membership/classes/class.swpm-log.php. Error message: Uncaught TypeError: fpassthruQ: Argument #1 ($stream) must be of type resource, bool given in /home/fk7vwt4wp8j5/public_html/wp-content/plugins/simple-
membership/ classes/ cl ass.swpm-log. php:39
Stack trace:
#0 /home/fk7vwt4wp8j5/public_html/wp-content/plugins/simple-membership/classes/class.swpm-log.php(39): fpassthruQ #1 /home/fk7vwt4wp8j5/public_html/wp-content/plugins/simple-membership/classes/class.swpm-settings.php(33): Swpmlog::output_log()
#2 /home/fk7vwt4wp8j5/public_html/wp-content/plugins/simple-membership/classes/class.simple-wp­
membership.php(197): SwpmSettings->init_config_hooksQ
#3 /home/fk7vwt4wp8j5/public_html/wp-includes/class-wp-hook.php(307): SimpleWpMembership->admin_init_hookQ
#4 /home/fk7vwt4wp8j5/public_html/wp-includes/class-wp-hook.php(331 ): WP _Hook->apply_filters()
#5 /home/fk7vwt4wp8j5/public_html/wp-includes/plugin.php(474): WP _Hook->do_action()
#6 /home/fk7vwt4wp8j5/public_html/wp-admin/admin.php(175): do_action()
#7 {main}
thrown

What’s up with that?