There are dozens of interrelated topics with every topic I discuss and it will take dozens of videos to cover everything.
Nothing we do, nothing we use, is “safe”.
Using a good external charger, IMHO, is safer than charging internal where we can’t easily monitor temperature, voltage, charging status, etc. It’s the lesser of two evils so I recommend using them instead of charging internally.
At a certain point though vapers get tired of hearing how risky everything we do really is and tune out. There is a fine balance between everything that I am always working on. Thanks for your feedback!