In some older bug reports (bug 38133, bug 40233, bug 61557, bug 68903, bug 87836) files with extension 'tsv' (tab-separated values, see: http://en.wikipedia.org/wiki/Tab-separated_values) are mentioned. It seemed to me that there is a special treatment in LibreOffice similar to csv files. If this is the case, files with these extensions should be treated completely equal to csv files.
This is currently not the case
(1) in the file filters of the file open dialogue, files with the extension tsv are not mentioned there;
(2) during saving, it is not possible to save a file the extension tsv.
Hint: This Bug has already been described in Bug 89312 together with other problems.
for me it looks like .tsv is subset of .csv
Could you attach testing .tsv file?
(In reply to raal from comment #1)
> for me it looks like .tsv is subset of .csv
> Could you attach testing .tsv file?
See parent bug 89312
Created attachment 113921 [details]
Small .tsv test file.
Yes a couple of additional delimited text formats need to be added to the "Spreadsheets" group filter.
The group filter list contains .csv and .xls, but should include addition of: