I think I have found a serious bug / problem with the latest firmware on the X-T4. I have found that the camera locks up when trying to take a photo with any of the advanced filters. When I set the left hand dial to advanced and use for example the "Partial Colour Red" option, the camera locks up immediately after taking the shot. I have tested using different lenses, sd cards etc etc - same result. I tested latest firmware update on my X100v using the partial Colour filter setting and that is fine. This feature is one that I don't use often but it seems to affect all the optional filters under advanced on the dial. All other camera modes work flawlessly. I cannot find anything about this yet online so will reach out to Fuji next. I wanted to post this here as thought its something other X-T4 users may like to test and report on so others don't have the same issue as I suspect that unless users make use of this feature, it won't be spotted very quickly. As an added note, once the camera locks up, simply removing and then replacing the battery gets you back in. Only this time until they fix it with a future update, avoid any of the advanced filter modes!!!!