And if you like Bash brace expansions; this one is sometimes quicker, 
than tab-completion and removing characters:

     $ mv file.txt{,.bak}
     file.txt.bak
     $ mv file.txt,{bak,img}
     file.txt.img
     $ mv file.txt{img,}
     file.txt

-Ramon

On 06/10/2022 14:45, Neil Bothwick wrote:
>> This is probably a case of Dolphin not being a good tool, unless it
>> has a built-in command-line?
>> $ mv newfile oldfile
>> will overwrite the old file in place with the new file with the name
>> of the old file.
> And tab-completion makes this a lot quicker than renaming files in a file
> manager.
>

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