In order to fix a broken attiny88, I tried to "Burn bootloader" with a working attiny to give it a try.
Unfortunately after doing that, the attiny can no longer be programmed by USB cable as before but only by ISP.
I notice that the red LED no longer flashes when I press reset for example.
So now I have 2 boards that can only be programmed by ISP, which is really not practical (going through an Arduino, connections to be made ...), whereas before it was enough to connect a USB cable and it worked for programming.
Here is what I did to burn my bootloader:
-Install the AttinyCore library
-Load the ArduinoISP script into my Arduino UNO
-Select: Board -> AttinyCore -> ATtiny48/88(No bootloader)
-Clicked on "burn bootloader" and the operation was successful
How can the attiny be programmed again by USB cable?
Solution: Put all the parameters as in the screenshot of @hmeijdam , and select Programmer: Arduino as ISP then click Burn bootloader.
I had already tried, unfortunately Optiboot does not change the problem and when I select Micronucleus, the IDE returns "> Please plug in the device (will time out in 60 seconds) ... " (the connections having obviously not been not changed).
I dug up my old MH-Tiny and first burned the bootloader via ISP
Please note that the MH-ET has it's own entry in the list of boards. It's the last of the T88 in the list
I select "fresh install via ISP". then I do Burn Bootloader
It seems to be selecting Fresh Install(via ISP, set fuses) as you showed in the screenshot, which is solved. I don't think I would have ever noticed it on my own, so really thank you.
So now I can program it again by USB and I was also able to repair the other one by the same method.