Hi – I have been having some issues on my late 2013 Imac since upgrading to Catalina. A lot of library messages in the logs for example. Sometimes if I go to shutdown I get a black screen for a while then it reboots, other times it’s fine. Sometimes when emptying the bin it just sits there on the screen and other odd behaviours. Have run Malwarebytes and nothing untoward there.
It’s got very frustrating so I thought I might try and download Catalina again and refresh it. Using the Recovery, Installed OS option, does this download a new copy of the OS to the Macintosh HD partition while keeping Macintosh HD-Data partition separate? I have a Time Machine backup and also other separate copies of the three users Photos library from the iMac but wanted to know if I can re-install the OS without specifically doing anything else to keep my data. Sorry if this is basic question but in Mac terms I am not that experienced.