Only one article category is processed for the Preview and for sending newsletter.
The categories are defined in
- Plugins: JMailAlerts - Content - Latest Articles / News
- Legacy / User options
- Choose categories
If categories A, B and C are chosen separately, then synced and Preview is checked, the articles of the individual categories are listed correctly.
If a choice of more categories are selected in the option, only one of the categories is processed and articles of only one category are listed in Preview and in newsletter.
The expectation is that all of the chosen categories will be processed and displayed in Preview and in the newsletter.