The trick is to use the rem unit introduced in CSS3, which refers to the root element size. In mPDF, 1rem is equivalent to the font size of the HTML body element. All other elements which appear as blocks in the columns, such as headings, subheadings, and info boxes, need to have a vertical size which adds up to an exact multiple of the body text or its line-height. Using rem makes the calculation easier, and also means that changes to body text size will scale other elements proportionally.

The trick is to use the rem unit introduced in CSS3, which refers to the root element size. In mPDF, 1rem is equivalent to the font size of the HTML body element. All other elements which appear as blocks in the columns, such as headings, subheadings, and info boxes, need to have a vertical size which adds up to an exact multiple of the body text or its line-height. Using rem makes the calculation easier, and also means that changes to body text size will scale other elements proportionally.

During the editing process, the 'draft' revision is loaded to replace the 'published' revision. Whenever a revision is saved, the 'published' revision is then reloaded and resaved to ensure that it remains published even though changes were made to the current revision.

On cron, a schedule allows the system to automatically switch to a given 'published' revision at a certain time.