Abbreviation in restructuretext can not render to latex pdf file.

[nvmt2024]

I had a problem using the "abbr" directive with latexpdf build.

The latex pdf file does not contain the abbreviation. But the html output file does.

Here art my text and result.

Raw .rst file: "Training :abbr:`MCU (Micro Controller Unit)` of the device is STM32F103RCT6".

In html: "Training MCU of the device is STM32F103RCT6"

In latex pdf: "Training of the device is STM32F103RCT6"

Thank you for your consideration!