I got this error when upload a folder

This full error:

Warning: preg_match(): Compilation failed: escape sequence is invalid in character class at offset 16 in /var/www/clouddata/system/classes/getid3/module.tag.id3v1.php on line 71

Warning: preg_match(): Compilation failed: escape sequence is invalid in character class at offset 16 in /var/www/clouddata/system/classes/getid3/module.tag.id3v1.php on line 71

Warning: preg_match(): Compilation failed: escape sequence is invalid in character class at offset 16 in /var/www/clouddata/system/classes/getid3/module.tag.id3v1.php on line 71

Warning: preg_match(): Compilation failed: escape sequence is invalid in character class at offset 16 in /var/www/clouddata/system/classes/getid3/module.tag.id3v1.php on line 71

Warning: preg_match(): Compilation failed: escape sequence is invalid in character class at offset 16 in /var/www/clouddata/system/classes/getid3/module.tag.id3v1.php on line 71

Warning: preg_match(): Compilation failed: escape sequence is invalid in character class at offset 16 in /var/www/clouddata/system/classes/getid3/module.tag.id3v1.php on line 71

Warning: preg_match(): Compilation failed: escape sequence is invalid in character class at offset 16 in /var/www/clouddata/system/classes/getid3/module.tag.id3v1.php on line 71
{"success":true,"msg":"The file was successfully uploaded."}

It'll working if disable error php using .htaccess:

php_flag display_startup_errors off
php_flag display_errors of

You can fix it in future.

Seems to be a PHP 7.3 small incompatibility. Will be fixed soon. Thank you for pointing it out!

The fix is included in the now available FileRun software update (https://docs.filerun.com/updating).