I've heard that glass bottles are better than plastic bottles. But won't glass bottles be a risk to the baby if he or she drops it while feeding?

This is quite debatable and both have their pros and cons. Sometimes the fear of chemicals make one switch to glass, but as you rightly mentioned, it’s difficult for a baby to handle weight and not drop it accidentally. You can make a choice with whatever suits. For older kids might support glass, but for younger ones the BPA free plastic bottles work perfectly