Slow Mac with Catalina

It may be beneficial for you to try a Safe Mode start.

Could you post a screenshot of "A column of numbered dropdown numbers overshadow and slow my work?"

The most recent version of Catalina is 10.15.6, which can be installed by using: macOS Catalina 10.15.6 Combo Update

To respond to your question, the current version of Catalina is 10.15.6. Installing it will not, however, speed up anything. In addition to the suggestions made here, I make the following thoughts. We don't know what your current OS is, how much RAM you have installed, what year and model of Mac you have, or what, if any, antivirus apps or Mac cleaner apps installed. So, it's impossible to offer any specific advice. I suggest that you download and run the free app EtraCheck and enable full disk access when running it. The post the report at the bottom of the page under Additional Text.

In the meantime, I can offer the following useful suggestions to help speed up your Mac. Often times there is a specific cause and other times any of the following actions may be helpful. They are “maintenance” steps which are often ignored.

·      It is important to occasionally restart a Mac. Ideally, once a week or more often. This does some system cleaning.

·      Regularly clearing the history of your browsers can help as all the data is stored in RAM. Clearing frees up RAM for system use.

·      Some people seldom empty their trash. If you haven’t, then do so. Also empty your email trash.

·      Some programs use a lot of RAM. (Like many Adobe apps.) When using then, close any other apps not being used.

·      Doing a restart in the safe mode can clear a number of problems. This is done by holding down the shift key at start up. This process can take up to ten minutes while the computer is doing its maintenance and cleans the cache. You may then restart normally.

·      It is also a good idea to run the Disk Utility app. If it reports some issues, then rerun it repeatedly as needed until the final report is ok.

·      On some computers the problem may simply be that there is not enough RAM installed for RAM hungry programs that are being used. The very minimum amount of RAM we would recommend for computers running the Catalina OS is 16 GB. This information is found by going to the Apple logo in the upper left corner of the finder and clicking on About This Mac. Note; not all computers are able to have RAM user installed. Some upgrades must be done by a qualified Apple service specialist.

·      Last, and most important, you should remove any and all maintenance and anti virus programs. They will cause problems and will significantly slow your computer. Also, they are not needed at all. The Mac's OS protects itself from any viruses.

Good luck. I hope this helps.

I would work on fixing any issues but if you want to you can revert to a previous MacOS.

Revert your Mac to a previous macOS version - Apple Support