[deleted] This was marked as "Solved" because there is nothing really to do - see https://metabullet.com/d/734-how-can-i-improve-my-website-speed/10
I'm not suggesting that simply changing the format of images will speed up the site, but if you had access to the information I was provided in confidence (which is why it is not listed here), you'd see that there really isn't any other optimisation that can be applied. Your suggestion is also completely incorrect - "will not hit the server again" - this is completely untrue as you are caching for one month. Once this time expires, the server will be polled again. I understand your enthusiasm, but if you want to provide a "fix", please ensure it is factually correct.
Manually resizing images is NOT wasting your time - it's a well known and accepted method of reducing your server load. This is why compression plugins for WordPress exist to compress images on the fly during upload, and conversion to WebP for example is another commonly used implementation. You should also be aware that edge caching images means that the same image is presented every time if it uses the same filename - even if you want to actually change that image. You'd need to clear the CF cache completely to resolve that, then by default, it'll poll your server again for that image meaning "will never hit the server again" is factually incorrect.
- There is nothing you can do to reduce unused JS, unlesss you are willing to remove extensions. This was not discussed, therefore, it's not an option.
- Deliver images in next-gen formats - hence my ONLY suggestion
- Properly size images - see above point, as this would be also the suggestion when reformatting the images
- Reduce unused CSS - there is no way of doing this without seriously impacting Flarum's core.
The only other suggestion would be to use
reflar/recache although this has issues, and is not free, which is why I didn't recommend it.
Given the results above, I'm sure you will agree that this topic was marked solved because as @Hari stated, he wasn't willing to perform the conversions for images, therefore, there's nothing else that needs to be done.
I'd like to remind you of the Platform Guidelines which you agreed on registration you would comply with located here