Function update 

pub fn update(
    project: &str,
    id: i32,
    content: &str,
    options: TimelineUpdateOptions,
) -> Result<TimelineEntry>

Replace a plain event’s text, and any other field given; an empty value clears it. The text is always required, so every call replaces it. Edit a placement with timeline.set.

Needs timeline.update or content:write in the manifest’s [permissions].