Hi @DW_Ferrell I'm sorry to hear about this!
I agree with @ilmari that it could be caused by having the editor open in more than one tab. If multiple people are editing the app at the same time, that could also cause changes to be lost (the changes would overwrite each other). We are actively working on multi-player, which will resolve these types of issues soon
App saves happen automatically so you don't need to manually save, but if you are ever concerned about a save you can manually trigger a save by clicking command + s.
In general, Retool maintains a detailed history of app saves, but here are some actions I'd recommend if you see missing edits:
1). Check to see if Retool is experiencing an outage (We're not currently having an app saves outage)
2). Check the browser console for errors
3). Review the history in the UI for changes (in the left panel)
4). As a last resort, Step back in the recent history of your app to see if a past page save is working better. To use this history feature, append ?_historyOffset=5 (you can choose any number, but I'm using 5 as an example) to the end of your app url. This will allow you to "travel back in time" 5 page saves. You can increase the number to go further back in time if you still don't see what you're looking for. The idea here is to go back to the most recent working version (lowest # possible) so you don't have to redo as much work (going back 1000 steps would likely show data, but it could be many, many changes behind). ***WARNING!*** If you make any changes to the canvas when traveling back in time, that past version will become your present version and it messes with the history, so be careful not to touch anything! Once you find a version that isn't crashing and you'd like to make that your present version, then you can make an edit to the canvas (move a component, add a component, etc) to persist that view.
We also have a release management feature on paid Retool plans to have more control of the end user view for apps. Enterprise teams that need more extensive functionality beyond our release management feature, should consider using source control to manage their apps.