Changing Template
The Templates button is where you can create, modify and apply saved settings to your accounts.
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Open Folder - Opens the /templates/ folder, you can save downloaded templates here, or delete/share templates from this directory.
Clicking a template name - Applies that template and its settings to the selected account(s).
Template Editor
This is where you can modify an existing template.
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Select the Template Editor and a new window will open, which looks similar to the account's General Settings.
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To edit a template, choose the template from the Select Template dropdown on the right-hand side.
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Then you change all of the settings to how you want them and then select the Save Template button on the right-hand side. This will save all of the settings as they are currently set. To only change certain settings select the Specific Settings Only? check box.
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You will now see all the settings with checkboxes next to them below. Select the checkboxes for the ones you want to edit.
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Now you will find that you can only interact with the selected settings, the rest are greyed out.
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Once you have edited the settings you want select the Save Template, this will only save the settings you have selected, the greyed-out ones will stay the same.
Creating Templates
You can create a template of an account, from within the account UI. In the Misc settings menu. See here