Recent files in Nautilus not working as a FIFO structure

["rpr //" <rpr nospam gmail com>]

Hello everyone!

Nautilus file manager (currently ver. 3.22.3-1 in Debian 9 with Gnome
desktop) offers the Recent files list.

As a user who is used to the recent files feature in some popular
applications (e.g. LibreOffice, MS Office, MS Windows Explorer) I
would expect it to work as a FIFO (first in, first out) structure: the
most recently opened document goes on top of the list and pushes the
previous list members downwards. And if the list size is limited, then
the last member is dropped from the list when the list gets full.

But the Recent files list in Nautilus uses another algorithm which I
find confusing. Here are some tests that demonstrate the issue:

Test 1:

Make sure the Recent files list in Nautilus is empty: select all items
and click Remove from Recent.

In bash shell create some empty test files:

cd ~/Documents; for i in {11..25}; do touch "test$i.txt"; done

In Nautilus open test11.txt, test12.txt ... test16.txt, test17.txt in
that order and close each file after opening. After that, the Recent
files list shows the following:
test17.txt
test16.txt
...
test12.txt
test11.txt
It seems that the most recently opened document is on top of the list.

But then if you open test11.txt again you see that the list does not
change (you would expect test11.txt to get on top of the list).

On the other hand, if you make a change in a file and save it, it gets
on top of the list.

Test 2:

Make sure the Recent files list in Nautilus is empty: select all items
and click Remove from Recent.

In bash shell change the time stamp of the test files so that the
first one is the newest and the last one is the oldest:

cd ~/Documents; for i in {11..25}; do touch -d "today 01:`expr 60 -
$i`" "test$i.txt"; done

In Nautilus open test11.txt, test12.txt ... test16.txt, test17.txt in
that order and close each file after opening. After that, the Recent
files list shows the following:
test11.txt
test12.txt
...
test16.txt
test17.txt

I conclude that the files in the Recent files list are actually sorted
by modification time from the newest to the oldest.

You can clear the Recent files list and try opening test files in some
random order: you will find out that the files are always sorted from
the newest to the oldest in the Recent files list.

I'd like to ask if this behaviour of the Recent files is by design or
is this a bug?

-- rpr.