I did not change any settings. I did install one or two libraries but that should not have an effect settings.
Before restart:
After restart:
What happened and how do I get it back to "normal"? It does unfortunately not state which setting was changed.
Log attached
2023-09-10_log - Copy.zip (147.3 KB)
After closing and opening the IDE, title bar and file menu were gone 
Closing and opening a second time solved it.
Still like to know what happened? I was already considering to go back to IDE 1.8.19 
I am experiencing the same issue. It seems to mostly happen after starting a new daily update (I only use the zip versions).
I do occasionally get the "no menu bar" on startup. Restarting solves that.
I have also experienced this a couple of times in the last month or so. I don't know what conditions it occurs under, but I can tell you that it happens when the window.titleBarStyle advanced setting ("Window: Title Bar Style") is set to "custom".
Thanks for the reply.
I just opened the IDE ( Version: 2.2.1-nightly-20230830) and got the above restart request, it does however have the menu bar visible (nothing changed since using it yesterday).
I checked and the "Title Bar Style" is set to "native"
Thanks guys fort confirming; it's the first time that I did experience it. I will keep an eye on it and check the "Window: Title Bar Style" when it happens again before acting on the popup.
@ptillisch, which configuration file do I need to check for that; might be better as a first check than going to advanced settings.
I did forget to mention that I'm running on Windows 10. Just in case of a follow up and I forget again
Same here.
I had the "Settings" tab of the advanced settings open in Arduino IDE each time I experienced it. I didn't intentionally change the setting, but I thought maybe I managed to accidentally change it though some change combination of keystrokes. Or maybe it was purely coincidental that I had that tab open (I end up with it open quite often due to performing various unusual operations during beta testing and support work and then not bothering to close the tab again after).
The file is settings.json. You can open the file in Arduino IDE by performing the following procedure:
Or if you want to access the file directly, you can find it at the following path:
Linux:
/home/<username>/.arduinoIDE/settings.json
macOS:
/Users/<username>/.arduinoIDE/settings.json
Windows:
C:\Users\<username>\.arduinoIDE\settings.json
It happened on my Windows 11 machine both times. But that also could be coincidental since I spend most of my time in that machine.
I do notice the interesting fact that "custom" is marked as the default value of the setting, even though it will be set to "native" on a fresh installation of Arduino IDE. It might be that this is the default in the underlying framework, but an override system has been put in place in the Arduino IDE codebase in order to avoid the poor user experience that results from that setting on Windows:
Just opened the IDE. I have three projects open (three instances). I received the "something changed - restart request" popup, which I simply canceled.
Also no menu bar visible which means I cannot select Save, Quit or anything else. This means I had to close the IDE using the task manager (the other option to close each window with the top right X closes each individually loosing the multi window open on restart).
Restarting opened all three instances again with the restart request popup and no menu for all three instances. Select the restart option in one of the instances closed it and then opened three new instances correctly, leaving the remaining two instances with the popup displayed. This is getting more of a problem.
Edit: I now cannot get out of this cycle - a real pain.
Edit 2:. After closing each instance individually (right click on the task bar icon and selecting close), then starting the IDE which resulted in a single instance with no menu bar, again closing it, then reopening the IDE it is now back to normal.
Just some additional points
<ALT><F4>.After load shredding I opened the IDE and again no menu. Using your Alt+F4 it does indeed close the IDE instances but only one at a time.
Restarting and after reloading all three instances I closed by selecting Quit. Restarting presented me with "restart" popups on all three instances. Ctrl+Q closed all instances (key combo for quit - good to know) and all loaded clean.
This never happened a few versions back. Something changed and not for the better.
Till now I've only experienced it once; never happened befor 2.2. What is your version?
Version: 2.2.1-nightly-20230830
Date: 2023-08-30T03:28:36.480Z
CLI Version: 0.34.0
Copyright © 2023 Arduino SA
I will update to the latest and see what happens.
Just a follow up. It happened again (two sketches open); titlebar disappeared.
<ctrl>S); no changes were made to the file.<alt><F4>).{
"editor.fontSize": 14,
"editor.autoSave": "on",
"editor.quickSuggestions": {
"other": true,
"comments": false,
"strings": false
},
"arduino.window.autoScale": true,
"arduino.window.zoomLevel": 0,
"arduino.compile.verbose": true,
"arduino.compile.warnings": "All",
"arduino.upload.verbose": true,
"arduino.upload.verify": true,
"arduino.language.log": false,
"arduino.sketchbook.showAllFiles": false,
"arduino.checkForUpdates": true,
"editor.trimAutoWhitespace": false,
"window.zoomLevel": 0,
"files.autoSave": "afterDelay",
"workbench.colorTheme": "arduino-theme-dark",
"window.titleBarStyle": "native"
}
Similar experience.
Three sketches open. They all open normally when I quit and restart.
Install a new version of the IDE - Zip file. Start the new version and all is wrong - no menu bar and Cancel/Restart popups in two instances. Every start the same problem. Quit each instance individually and then restart, opening only the last single instance. Still a problem. Close and then restart and it works.
Open all three instances and it starts OK. Occasionally I still get the Cancel/Restart popup in some instances. I always select Cancel since Restart screws my preferences.
Just opened IDE again and all three instances open no problem.
An additional observation
It happened twice today; in both cases I canceled the restart of the IDE. After the second time I noticed that the <tab> key behaviour changed; it did not happen after the first time. The <tab> key 'jumps' between the serial monitor (input textbox) and the code window (both directions).
I have not seen the problem when I work with a single instance for a while now.
However, if I have, say, three instances open, close them with File/Quit, and then open the IDE (which restores the three instances) I always get the "Setting changed" popup.
I do not always get it, even with multiple sketches; but it indeed only seems to happen with multiple sketches open.
Yesterday I had multiple instances open of sketches with very similar names (just versioning in them to differentiate). I know I went back to just one open and later re-opened an older version (so two open); that's when I noticed the <tab> key behaviour (that was the first time I've observed that).
I have not experienced the key problem. Saying that, I do not regularly use it - I will keep an eye on it.
I've experienced this json/RESTART bug occasionally, it always occurs at first start for the day, and is more likely when multiple sketches are open. (Im not sure if I've ever seen it with nly one window open)
I've found it's best to select cancel in the restart dialogue, close & restart the IDE. If it restarts with the menu bar missing I just restart again.