I want to reinstall Linux 18.04 on my laptop after I screwed up several things (see this question, also help is welcome with that), but when I boot with the USB live I don't see the option for keeping the files (I don't want to format again). I am not sure if this has something to do with the fact that the system in the laptop is version 18.04.4 and the one in USB is 18.04.3. Can anyone confirm if this is the issue and if so whether it can be solved with an iso of version 18.04.4, and where could I find it?
SnapOverflow
To reinstall without reformatting, you need to select "Something else" between the installation options. This brings you to the manual partitioning screen. There, you have to indicate yourself which partitions are to be used, and doing so, you can uncheck the "Format" checkbox to prevent the installer from reformatting prior to reinstall.