[Users] Getting Claws Mail to remember external application for 'open with ...' dialogue

[John Hostler]

Hi everyone, I was a long time user of Thunderbird and I have recently switched to Claws Mail. My computer runs Linux Xubuntu 17.04 and I have
installed Claws Mail from the Ubuntu software centre, it's version 3.14.1.

Generally it works very well but there is one thing I find tiresome, I'm not sure if it's a bug, I hope someone can advise me.

When I receive an email with an attachment like a word document or a spreadsheet I press the 'O' hotkey and Claws Mail suggests the correct external
application to open the file (in my case it's LibreOffice Writer or Calc). I want it to remember that setting and to use the same application every
time I need to open that kind of file. In the 'open with ...' dialogue window that appears, there is a 'remember this' tick box: but whether I select
that option or not, Claws Mail doesn't remember. Instead, every time I want to open an attachment -- even if it's the same attachment in the same
email I opened before -- it again suggests the correct external application and again asks me to confirm.

I remember that Thunderbird asked me to confirm which external applications to use, when it was first installed, but after that it opened them
automatically. Is there any way to persuade Claws Mail to behave likewise? The fact that there is a 'remember this' tick box indicates that the
developers intended this to happen, but it doesn't work in my case.

Thank you in advance for your guidance. John.