creating mail template

I'm asked to update a mail template (add two new fields).

First time I look into this and the Sugar knowledge db doesn't offer me info I need.

From the below lines coming from that template : what's the structure of such a line ?

Dear Credit Manager,


My opportunity for Account: {::future::Opportunities::accounts::name::} has reached 30% feasibility and I will now provide a quote to the Account. If there are any credit concerns for this Account, please advise.

Opportunity: {::future::Opportunities::name::}
Account: {::future::Opportunities::accounts::name::}
SAP ID: {::future::Opportunities::accounts::account_code_c::}
City: {::future::Opportunities::accounts::billing_address_city::}
State: {::future::Opportunities::accounts::billing_address_state::}
Account Type: {::future::Opportunities::accounts::account_sub_type_local_c::}

Current Sales Stage: {::future::Opportunities::sales_stage::}
Opportunity Value: {::future::Opportunities::amount::} 
Opportunity Owner: {::future::Opportunities::assigned_user_name::}

Click here to see the record
{::href_link::Opportunities::href_link::}

What is ::future:: meaning ? Should I typ this in by hand or is it added automatically one way or another ?

When I hit Insert after selecting a field via the Insert Variable (7,9 release) it only inserts the field name like this

$account_name

In that "Insert Variable" section of the edit template screen , I cannot select the Opportunities module, although those fields are used above...I can only choose Account, Leads or User... ?

so... I'm confused how this existing mail template was created (4 years ago)

Even more confused since the Knowledge DB seems to show a different screen when they talk about inserting new variables

(https://support.sugarcrm.com/Documentation/Sugar_Versions/7.9/Ent/Administration_Guide/Developer_Tools/Workflow_Management/index.html#Inserting_Variables)

Can somebody clairify this for me please ?

Thanks!

Hugo