Is anyone else having trouble opening existing journal entries to edit them? It seems like it is causing high memory usage and takes a long time to load if they ever do.

There are a few reasons why you're having trouble opening existing journal entries in QuickBooks Online, @info2020. Let me share some information to help you resolve this. 

This can be caused by the browser you're using. Clearing your browser's cache and cookies can sometimes improve performance, as it removes temporary files that may be causing conflicts. Begin by signing in to your QuickBooks Online (QBO) account using a private browser. It'll help isolate the issue as it doesn’t store data in the cache.

The following are the shortcut keys for opening an incognito or private window in different web browsers:

Google Chrome and Microsoft Edge: 

• Windows/Linux: Press Ctrl + Shift + N
• macOS: Press Command + Shift + N

Mozilla Firefox:

• Windows/Linux: Press Ctrl + Shift + P
• macOS: Press Command + Shift + P

Safari: Press Command + Shift + N

If it works, here's how to clear cache and cookies to fix issues when using QuickBooks Online. You may need to refresh any open web pages for the changes to take effect. 

Additionally, please ensure that you have the latest browser update installed and that the computer you're using meets the minimum system requirements recommended for QuickBooks Online.

For more information about reversing a journal entry to swap debits and credits or delete it entirely, refer to this article: Reverse or delete a journal entry in QuickBooks Online. 

I'm always here if you need more help opening and editing journal entries in QuickBooks Online. Have a great rest of the day!