This has also just started happening for me and I am using 29.7 - Why?!!!
Both the swatches and the ‘Show Swatch Options’ icon at the bottom disappear if I am working on a file and have not saved. Once I save they appear to come back again and are editable or, the Swatch Option icon becomes editable and I can implement the workaround suggested by @kirstenli below.
Question is - I haven’t updated my Illustrator software for some time, mainly because I simply do not trust that the teams introducing these updates will not break something else when they do ‘fix’ the current versions, so why is this happening now? What are Adobe doing surreptitiously on my machine or to my software that is causing this glitch?
Disclaimer: Please note that renaming preferences folders will remove all the custom settings, and Illustrator will launch with default settings. You can also save a backup of the folders in case you want to. The location is mentioned above.
Additionally, try updating to Illustrator 29.8.5 and share your observations.
I cannot see 29.9.8 on my updates dashboard - only 30.2.1
I did reset the preferences but that didn’t resolve the issue. The swatches still disappear whilst working and the only way to make them visible again is to save the document, then they appear again.
I have now updated to the newest version and it appears to be ok at the moment but I’ll let you know if I still encounter the problem, although updating has flagged up new issues which I need to post in another thread 🙄.
@kirstenli this is a known bug with Adobe Illustrator 29.7.1. The easiest fix is to go to your Swatches panel. In the bottom-right corner of the panel, you'll see a couple of small icons. The first one that looks like a rubik's cube, you can choose to show what swatches. You may have accidentally enabled a filter to only show patterns, gradients, or other types of swatches.
Or, in the swatches panel, on the bottom-left corner is a a stack of a library books (kinda looking). Click on it and selected the swatches library. A new panel will open with the default swatches. You can then select all of them and drag them into your main Swatches panel if you want them there.
A more drastic step, but it can resolve many unexpected behaviors and corrupted settings. On PC: Press and hold Alt Control Shift as you launch Illustrator. On MAC: Press and hold Option Command Shift as you launch Illustrator. You will be asked if you want to reset your preferences. Confirm, and Illustrator will launch with its factory settings. This will reset all your custom settings, including workspace layouts and other preferences, but it can often fix bugs that are caused by corrupted preference files.