Bug 504869

SUMMARY

I already mentioned this in a comment to https://bugs.kde.org/show_bug.cgi?id=483706 and, if I remember correctly, it was me who reopened that issue because of it, but there has been no reply. So here I am trying to report this as a separate issue (probably what I should have done in the first place). This is very serious and needs to be fixed, don't underestimate the danger of it please.

Relatively recently, the option "extract here (autodetect subfolder)" was removed from the context menu and the "extract here" option was changed to have basically the behavior of the old "extract here (autodetect subfolder)".

However, the new "extract here" option has a crucial flaw, in that, if a folder already exist with the name of the one that is going to be created, it will be written into without warning. If there are files and subdirectories with conflicting filenames inside the directory, you will get the OS's usual prompt about whether to overwrite etc, but otherwise (and anyway for the names that don't conflict), the files will be extracted into the existing directory silently. Either way, the result can be an absolute disaster, potentially unrecoverable.

Before you underestimate the seriousness of this, you need to consider that even if a folder exists with the same name, it could be a totally unrelated folder, in which case it's likely that many of the files and subfolder that you are going to extract have non-conflicting names, and these will just be extracted into the existing folder before you realize it and with no opportunity to stop it. So, even if you don't end up overwriting anything (because you do get a prompt before _that_ happens), you can end up with a mess that will take a lot of work to clean up.


STEPS TO REPRODUCE
1. have a zip file called mything.zip containing the following:
```
# contents of mything.zip
- mything         # folder
-- file1.txt
-- file2.txt
```
2. Next to it, within the same parent folder, have a folder called "mything"
3. Right-click on `mything.zip` and do "extract here"

OBSERVED RESULT
The files extracted from the zip file will be written into the existing folder "mything" with no prompt. If there are files or subfolder with conflicting names, the OS will ask you whether to rename them, overwrite (or write into in the case of directories) or skip; otherwise, the entire thing will happen silently. Either way, you won't be given a warning that the root folder already exist nor a choice of what to do.

EXPECTED RESULT
You should get a prompt telling you that a folder called "mything" already exist, and a choice whether to write into it, rename the folder being extracted, or cancel. Or at the very least, a warning and a choice whether to continue or cancel.

Note that the behavior of the old "extract here, autodetect subfolder" was to automatically rename the extracted directory appending a "(1)" (or "(2)" etc.) to the name. While it wasn't the best behavior possible in that it didn't give you a choice or a warning, it was a perfectly acceptable behavior.

SOFTWARE/OS VERSIONS
Operating System: Manjaro Linux 
KDE Plasma Version: 6.3.5
KDE Frameworks Version: 6.14.0
Qt Version: 6.9.0
Kernel Version: 6.6.90-1-MANJARO (64-bit)
Graphics Platform: Wayland
Processors: 12 × 12th Gen Intel® Core™ i7-1255U
Memory: 15.3 GiB of RAM
Graphics Processor: Intel® Iris® Xe Graphics
Manufacturer: ASUSTeK COMPUTER INC.
Product Name: Vivobook_ASUSLaptop X1502ZA_F1502ZA
System Version: 1.0