as shown in the screenshot  you cannot see the extention of the file so same named files with long name and different extention cannot be distinguished
well it has a workaround, you can hover the file and see the bubble but I have a suggestion:
in many apps and programms when a filename is displayed at least the extention is visible in the end like so: google-docs-sear...6_x64.odt
also in the same example you can add the last few chars, so, if two files are named almost the same but some chars in the end are different, you can see the difference!
proposed changes mockup
all images together
Steps to Reproduce:
1. open libreoffice (you see the recent files) see 
2. no extention visible if the file name is big
pic [1.1] no way to see last chars or at least extention so same named files with different extention or almost same named files look the same (if they have the same thumbnail then they are indistinguishable)
show last few chars and extention as shown in a quick mockup [3.1]
User Profile Reset: No
Version: 184.108.40.206 (x64)
Build ID: 2412653d852ce75f65fbfa83fb7e7b669a126d64
CPU threads: 4; OS: Windows 10.0; UI render: GL; VCL: win;
Locale: en-US (en_US); UI-Language: en-US
Created attachment 151994 [details]
 screenshot the same as image  in bug
its the same image as the screenshot  in the bug
Created attachment 151995 [details]
 the suggested changes - mockup, same as the mockup  in the bug report
its the same image as the mockup 
+1 from me
UX-team, what do you think?
Not a fan. We already provide the full path with extension (if any) as a Tool-tip on mouse over of the thumbnail. Labeling with the file name--suplemented with the full path name & extension was the design decision when we laid out the StartCenter.
See no reason to change that now.
IMHO => WF
I also think extension should be visible. I had never noticed it was visible with the tooltip.
IMHO, we should even see the extension as a very visible tag upon the preview icon.
What you likely want to know is the module in which the file would be loaded. Meaning odt = Writer, ods = Calc etc. That applies also to docx and xlsx but how about hdg or nyz? (fictional file extension you never heard about). So wouldn't the best solution be a small overlay MIME type icon indicating the LibreOffice module?
Most of the time, yes.
But sometimes I need to make a distinction between an odt file, a doc file, a text file that have the same name.
(In reply to Olivier R. from comment #7)
> Most of the time, yes.
So let's have an overlay with the MIME type icon for the relevant cases and stick to the tooltip if in doubt according comment 4.
Created attachment 153029 [details]
That's how it would look with icon overlay. The actual filename and extension is still available per tooltip.
Patch is under review at https://gerrit.libreoffice.org/#/c/76537/
Heiko Tietze committed a patch related to this issue.
It has been pushed to "master":
Resolves: tdf#125756 - MIME type icons on start center's thumbnails
It will be available in 6.4.0.
The patch should be included in the daily builds available at
https://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More
information about daily builds can be found at:
Affected users are encouraged to test the fix and report feedback.
A note: the overlay icons are not the same as used in the left sidebar of the Start Center that launch respective modules (more detailed? maybe other icons, or other resolution?)
(In reply to Mike Kaganski from comment #11)
> ... maybe other icons, or other resolution?
Any proposal? Would be nice, indeed, to have icons not only for LibreOffice modules but all known file formats.
(In reply to Heiko Tietze from comment #12)
> Any proposal? Would be nice, indeed, to have icons not only for LibreOffice
> modules but all known file formats.
In https://gerrit.libreoffice.org/c/core/+/76537, you used the full-sized icons (128 pixel) from BitmapForExtension/EncryptedBitmapForExtension. Then you scaled those bitmaps to 40 pixel resolution, with all the raster image downsampling side effects.
But indeed, we also have lower-resolution icons for the same things, like those shown in the "Create" panel on the same start center screen (I don't know which their resource ids are, but I'm sure Andreas or Rizal could help here?). So using, say, 32-pixel icons here without any scaling would result in sharp overlays without downsampling artifacts.
Note that I'm not talking about more fine-grained MIME icons like for every supported filetype; only about per-application icons, just as you used in the change.