v2.6.0

Added

• Categories can be put in order, and deleted. Dragging a category in the Linux sidebar, or by
  its handle in Android's "Edit Categories…" (in the category filter's menu, where a category is
  also added, renamed or deleted), saves the order in the account's todav/config.json, so every
  device follows it. Deleting one (Delete in its menu on Linux) keeps its tasks: a task with
  other categories takes the next as its own. Adding, renaming, reordering and deleting can be
  undone.
• Android: the category filter's menu has "Other", and the add sheet's category chip always
  shows, with "New Category…".

Removed

• Android: the sync button in the task list's top bar; pull to refresh does it.

Fixed

• Android: the month planner widget left a gap to its right (the Pixel Launcher reports it 16 dp
  narrower than it is); its days now fill the width.
• Android: the month planner widget's weekday names lined up with its days only at the width the
  launcher reported; they now share the days' column width.
• Android: a list's category headings, filter and pickers showed only the categories saved in
  the account's config, so a list whose tasks had other categories (typed on a task, from
  another app, or on this device) looked ungrouped. They now include the categories its tasks
  have, as on Linux.
• A category added in the sidebar or made on a task is kept and shown last, instead of among the
  others by name until a task was dropped on it; renaming one keeps its place in the order,
  and a task's other categories are renamed with it.