The first implementation of custom themes was actually using javascript instead of liquid markup. I’ve moved away from javascript to liquid markup so it works with “internal PDF generator” which could only take plain HTML as input.
And “Internal PDF generator” existed because web-browsers were not good enough at printing HTML content properly.
After some years the landscape has changed. Web-browsers got so much better to the point that Print button was more and more viable. So I’m simply observing where the technology is heading, internal PDF generator which was causing me a lot of headaches has been made obsolete and the only reason why custom themes are using liquid markup is therefore no longer justified.
Customization of invoices will be through javascript which is easier to understand and debug than liquid markup. I mean anybody who knows how to make websites will be able to customize the look of invoices (or other documents) without knowing anything about Manager. That means there will be more talent available for businesses to choose from to implement customizations.
I’m not yet there. This is multi-step process to get there but once I get there, all users will naturally prefer javascript over liquid markup for their customization needs. Liquid markup is unfortunately all or nothing proposition - you have to have the entire invoice rewritten even for the tiniest customizations. Javascript allows progressive enhancement.
Also, sometime next month there will be improvements to footers which will kind of make it more obvious where I’m heading with this.