I didn't found a way to keep battery saver permanently active, but you can use the Stylish extension in Opera.

• Stylish extension: https://addons.opera.com/en-gb/extensions/details/stylish/
• Sownload Stylesheets: https://userstyles.org/

Maybe is because Opera don't come with a h264 codec, so you need to install it manually. Installing gstreamer plugins should solve it.

You need to install 'adobe-flashplugin' package.

You need to install chromium-pepper-flash. If you didn't already, enable russian fedora repository:

su -c 'yum install --nogpgcheck
http://mirror.yandex.ru/fedora/russianfedora/russianfedora/free/fedora/russianfedora-free-release-stable.noarch.rpm http://mirror.yandex.ru/fedora/russianfedora/russianfedora/nonfree/fedora/russianfedora-nonfree-release-stable.noarch.rpm'

then, install it with:

sudo yum install chromium-pepper-flash

It suppose to work automatically.

I didn't found a way to keep battery saver permanently active, but you can use the Stylish extension in Opera.

• Stylish extension: https://addons.opera.com/en-gb/extensions/details/stylish/
• Sownload Stylesheets: https://userstyles.org/