Request for Subtitle and Quality Control

Discussion

I’m new to this site, and I have to say it’s pretty good so far.
However, there are two essential features that I believe are missing:

Subtitle On/Off Switch
I mean, you already give us the ability to change the subtitle size, so it should be easy enough to add a simple toggle switch.
Why do I have to keep subtitles on while watching a dubbed version?
Video Quality Control
I live in a region where the internet connection is not always stable, and bandwidth is limited.
So please add an option for users to choose the video quality manually.