Did you check in logs or v3 profile that the Chrome execution is really the main bottleneck?
Do we talk about one main template without additional extra pdf utils template merges?
Don't you use high-resolution images with the sizing problems mentioned here?
To assure the aria is really hidden, please open the output pdf with Notepad and search for the text "/StructTreeRoot". You shouldn't find it there.
However, I am afraid it can easily happen phantom is faster than Chrome. Our invoice example is also a bit faster with Phantom. Phantom is more lightweight and doesn't need to care about many modern things Chrome does. You may try to play with CSS and HTML. Chrome is slower on long
<table> or some specific style combinations, but there is no rule of thumb. You may try to remove styles one by one to identify the problematic parts, but it may as well end up without success.
Some arguments for migration even with higher rendering times:
- phantomjs supports just old js/css which was used a decade ago
- phantomjs is a potential security weakness, there are no security updates for many years
- phantomjs may not work with future OS updates, it already breaks on https connections since Ubuntu Beawer which was released in 2018. (can be solved with implementing explicit proxying requests so far)