I kept getting “missing the last block,” or some such, and after watching the light in the wifi dongle, realized that after it said “downloaded,” it werent!! So, I just let it run without stopping. Next morning, kde imagewriter, I had an installable iso!
Point being, do not shut your system down until the blinking lights on your dongle/router are not blinking anymore, capiche?
that will teach us! 
what we already knew …
I can dig it! But…Why does it say it’s downloaded when it’s not? 
we don’t know what happened
and can’t know
maybe it was (downloaded)?
we don’t know
you don’t know
Thunar said it was downloaded…I will not use thunar as the arbiter any longer; only the absence of the flickering lights on the dongle, or the successful use of the iso loading the software. That I know. A lot of edginess here today…Nachlese, you are not usually one of the edgy ones!!
Thanks to all!
Thunar in KDE? Why?
I feel like I got clickbaited. 
If I’m reading this right, you would technically have to do a sudo sync as well. With USB drives, you can do it through the GUI with the eject option.
A graceful shutdown should eliminate the need for either though… ?
This is an ever returning topic - which roots in the Linux kernels agressive caching of files.
The topic is mostly related to removable media - we rarely see it otherwise.
//EDIT I realize I may have misunderstood the question somehow.
I am confused
Thunar doesn’t download anything?
Is it the write to an USB (slow) storage?
This only makes sense if you pointed the browser to a ventoy prepared stick.
Not that makes even less sense - what does that have to do with download?
If your topic is about how long time it takes to write an ISO to USB then my first assumption at the top of this comment is correct.
Your system has cached the image - imagewriter has flushed all data to buffer - the buffer has not yet been written to stick - and that is normal - imagewrite has delivered the final part to the system so technically - seen from imagewriter point of view - the job is done.
You just yanked the stick premature to the buffer being flushed to stick.
I find that security on some browsers will download a file, but present an easily overlooked warning immediately before completion. Sometimes one needs to click it to allow completion.
Ah, yes! I installed this in the xfce manjaro! But then I re-installed xfce manjaro and forgot about it ( * [[root tip] [How To] Disable write cache for USB storage devices )
Just installed it on the kde-manjaro edition…Thanks for this!
Re “thunar downloading,” I mean thunar showed a completed file name, rather than the partially downloaded filename.
kgw