У вашего броузера проблема в совместимости с HTML5
By default when you want to import sql file size is 2MB in PHPMyAdmin.
That is PHP’s file upload limit.
To change maximum import file size do following step:
1.Find php.ini file: Type locate php.ini this command to find php.ini file.
2.Edit php.ini file: Type sudo gedit /etc/php/7.0/apache2/php.in this command to edit php.ini file.
3. Find following variables and change values as you need: Type this command to change values as you need.
post_max_size = 200M
upload_max_filesize = 200M
max_execution_time = 200
max_input_time = 200
memory_limit = 200M
4. Restart apache to take effect:
Type
sudo service apache2 restart
this command for restart apache server.