Canon RF 24-240mm F4-6.3 IS USM Q&As

I recently dipped my toes into more serious digital photography, and picked up: EOS RP RF 24-240 F4-6.3 IS USM RF 35 F1.8 IS STM MACRO I'm using the 24-240 as a jack-of-all-trades lens, for family pictures when we're out hiking, or candids of the kids out playing, pictures of my wife baking, or taking as a one-lens solution on road trips and vacations. The 35 gets used for low-light shots, indoors after hours, around the campfire, or for street walks. So far, I've been thrilled with the...

Just got a RF 24-240 for travel and noticed when I shoot at max zoom w/ my R5 I frequently end up with a frame of digital artifacts surrounding the picture. It's only noticible in processing. I don't see it in-camera, either when shooting or reviewing. It also doesn't occur 100% of the time -- maybe 95%. And it's only at 240mm exactly. Aperture doesn't matter. I don't see this with any of my other RF lenses so I'm sure it's not my camera. I know the RF 24-240 is a quirky lens at max wide,...

For anyone using the Canon RF 24-240mm lens, is it possible to use smaller than 72mm lens filters on it without significant vignetting? It looks like the glass up front is significantly narrower than where the lens filter threads are. But I also know the lens already had vignetting that has to be corrected. But that doesn't necessarily mean that the hard vignette is the outside edge. On my 35mm eg I can use smaller filters with a step down, which is what I'd like to do with the 24-240mm. Thanks!

Is the R6 available as a kit with the RF 24-240 anywhere on the North American market? Thanks in advance.