I also suggest better to upgrade and mostly it might fix your issue. Kindly use the following keyboard combination as per your requirements.
Basically, as per Apple Guidance:
Command (⌘)-R Install the latest macOS that was installed on your Mac.
Option-⌘-R Upgrade to the latest macOS that is compatible with your Mac.
Shift-Option-⌘-R Install the macOS ...
Considering Ubuntu in your question.
When you run Ubuntu installation, it asks where you want to install the Bootloader. You can choose your Mac Boot loader partition. It will add extra entry for Ubuntu. Make sure you get a backup of your EFI partition before playing with it so you can recover it without running a complete installation of OSX again (though ...
format the new ssd when still outside the mac (you need an cable to usb). Forget all software that came on the disk: all has to go with the format.
Now use a clone app on the mac, like CarbonCopyCloner, to make a clone of your actual disk with everything on it to the still external disk.
When that is ready, shutdown the mac.
Restart while ...
I read your this article. Follow the steps outlined in the article with these adjustments. I'd set up three partitions instead of four: macOS, swap and Windows. I'd adjust the macOS partition to the size you want to for linux. I'd install linux over the top of the macOS partition.
I've set up a triple boot system before but I haven't tried this procedure. ...
Windows can't read APFS.
To get back to macOS you need to hold the Opt ⌥ key at startup.
BTW, don't ever let Windows adjust anything on your drive. Consider that Disk Management tool as a read-only utility. It doesn't understand how it's being fooled into thinking it's in charge & will break things.
When you have an encrypted disk with FileVault, the system needs to ask for an authorised user to login just after EFI boot. (no news here, just enforcing what most people know)
That logo shows your avatar because your user's avatar is inserted on the EFI boot image/nvram. At this point of the boot sequence, there is no Operating System loaded yet, it's ...
If the above don't work, which I imagine resetting the NVRAM won't since that's what you do each time, you can try the following:
Your Mac might be in Safe Sleep. To wake from Safe Sleep, connect
your Mac to its power adapter and press the power button. Make sure
that your Mac isn't turned off. If your MacBook Pro still won't wake
up, follow these steps to ...
I know you've already reset the NVRAM, but the first thing I'd try is to reset both the NVRAM and SMC in that order. Before following the steps below, ensure you have no external hardware connected and make sure you use the built-in keyboard.
Reset the NVRAM
Your Mac uses Non-Volatile Random-Access Memory (NVRAM). Here’s how to reset the NVRAM on your ...
Troubleshooting is often a process of elimination and does require patience, so you'll need to keep that in mind as you proceed.
The first thing I would do now is test your Mac in Safe Mode.
Boot into Safe Mode
Follow these steps to boot your Mac into Safe Mode:
Fully shut down your Mac
Restart your Mac
Immediately press the Shift key and keep it down
I have the same problem on a 2014 iMac running Mojave. Its 3TB fusion main drive filled up as I was downloading a 5 GB file. The write failed to complete and immediately the disk became read-only.
Now no command in disk utility or in single user or recovery mode can escape read-only mode, so no repair or reformat or OS reinstall is possible. I see no ...