Trying to insert external data does not work properly (Needs to long time)
Try to insert
1) Open Calc
2) Insert -> Link to external data
3) Paste Url
4) See it does not work
From the version reported here, through all versions to the current Version 184.108.40.206 (Build ID: da8c1e6) this problem has existed. Opening a NEW spreadsheet and inserting a "Link to external data" does function correctly. However, after opening a previously saved spreadsheet this function does not work. After entering the URL nothing happens, waiting 10 minutes does nothing, but you can Cancel the operation. As a work round, open a new spreadsheet, use the "Link to external data" and provide the URL. This opens the URL at which point you can Cancel the operation. Now open the previously saved spreadsheet and use the "Link to external data" function again and it now works correctly.
Isn't the Insert > Link to External Data... menu (a.k.a. Web Query) supposed to only support HTML tables of data and not CSV array formats? The help page (https://help.libreoffice.org/Calc/Inserting_External_Data_in_Table_WebQuery) has this to say:
"With the help of the Web Page Query (LibreOffice Calc) import filter, you can insert tables from HTML documents in a Calc spreadsheet."
I would think that only the first of the three provided example links fit this criteria. If I delete the "&ctype=csv" part from the end of the third link then the link returns a list of HTML tables to chose from as expected and inserts a link as expected. The link does not work under v4.0 (displays "The link could not be updated"), but that is due to bug #63407. Note also that any link containing certain non-URL-friendly characters will also not work as per bug #42377.
The initial point about the function taking a long time may be valid as it can take a while.
Insert -> Link to external data
is not meant to work with CSV files or files of types other than spreadsheet or HTML files. As also the online-help states the source file needs to have an identifiable table or cell range that can be addressed, i.e. to update the data.
Note that an entire CSV file's content can be inserted using Insert -> Sheet from file, and can be linked (and then updated) as well by checking Link in that dialog.
I'm closing this as notabug.