Anki

- Fix duplicate text when pasting with Ctrl+Shift+V (thanks to Henrik).
- Remember last colors in editing window (thanks to Henrik).
- Show flag and mark icons in preview window (thanks to Hikaru).
- Center first match when searching in sidebar (thanks to Abdo).
- Added F9/Shift+F9 shortcuts for sticky fields, and increase opacity (thanks to
Henrik).
- Fixed starting ease specified in deck options not being used by v3 scheduler.
- Fixed learning cutoff not updating during review, and some learning cards
remaining at the end of review in the v3 scheduler.
- Fixed Change Notetype not mapping fields correctly when count differed.
- The congrats screen now updates periodically again.
- Fixed Redo menu item showing Undo action name.
- Fixed notetype selection in the import screen.
- Fixed error in overview/congrats screen when there is no current deck.

Undo handling:

- Most actions now support multiple undo steps. You can change a card template,
delete some notes, bury a card, then undo each of those steps if you wish.
- Actions that support multiple undo steps will now save the changes
immediately, meaning that if Anki crashes, the changes you made in the last
few minutes will no longer be lost.
- Most undoable actions can now be redone, so you can undo an accidental undo.
- Actions that don't support the new undo handling (eg, Check Database), will
clear the undo history.
- Add-ons will clear the undo history if they modify the database directly, or
use routines that don't support undoing. There are some new routines available
to add-ons to make operations undoable, but add-ons may need to be updated
to use them.

Scheduling changes:

- A new scheduler is available, with a number of improvements. Please see the
[2021 scheduler page](https://faqs.ankiweb.net/the-2021-scheduler.html) for
more information.
- The deck list now shows the learning count separately.
- On new collections, the v2 scheduler is now the default.
- Set due date uses the deck's configured starting ease (thanks to cyphar).

Browser changes, mostly thanks to Rumo:

- The sidebar now has two modes. The default allows clicking on items to search
for them. The other mode allows you to select multiple items at once, so you
can drag & drop or delete multiple items.
- The browse screen can now be toggled between showing cards,
and showing notes.
- When showing notes, some columns will show an aggregate over all the
cards of a note.
- Added an introduced:x search to locate cards first studied in the last x days.
- Column rendering has been moved into the backend, and will be faster than
before (but is still limited by the speed of the graphics toolkit).
- A fair bit of the browser code has been changed, and some add-ons like the
"Advanced Browser" add-on will need to be updated to support the new approach.
- New tag icons and associated backend work (thanks to Henrik).
- Added an option in the Preferences screen to customize the starting
search text (eg, to start with "deck:current").
- More reliably scroll to the current card.
- When opening the Browse screen with an active study card, the whole
deck is now shown.
- Added 3 new flag colours.
- Flags can now be renamed in the sidebar.
- Horizontal scrolling in the browse screen is less jumpy.
- Sidebar items can be dragged onto the Saved Searches area to add them as a favourite.

Editor changes, mostly thanks to Henrik:

- A new editor toolbar implementation, with improved icons and handling.
- The editor now provides bullet and numbered list buttons.
- The editor now provides buttons to control text alignment and indent.
- Sticky fields can now be toggled on/off from the editing screen.
- A new API is available for add-ons, and the existing API should continue
to work.
- The HTML editor is now shown inline, and supports syntax highlighting,
and showing opening/closing tags.
- Warn user when they attempt to use cloze markers inappropriately
(thanks to Rumo).

State handling:

- When you make changes, the user interface should update more consistently now.
Adding a new tag to a note will update the sidebar in the Browse screen for
example, and when you review a card that is shown there, the columns will
update.
- The Browse screen no longer refreshes a search automatically. When you make a
change, the column text may update, but the number of rows will not change.
Deleted cards show "(deleted)" until you search again.
- The main window no longer shows a "waiting for editing to finish" screen. When
you make changes such as editing a note, the main window will dim, and will
automatically refresh when you return to it.

The deck options screen has been reimplemented:

- (Re)learning steps are now shown with units, eg 10m or 4d.
- Deck options are now shown on one scrollable page.
- Extra help is available for most options.
- It is easy to see at a glance which options have been changed from the
default, and individual options can be reverted to the default setting.
- Warnings will be shown for some common issues (eg, review limit too low
compared to new cards).
- Some of the more advanced options have been moved to a separate "Advanced"
section.
- The old options can be accessed with a Shift+click, since it will take a while
for add-ons to be updated to support the new screen. A new API is available,
thanks to Henrik.
- The deck description is now accessible via a button in the overview screen,
instead of via the deck options.

Other features:

- An updated Change Notetype implementation, that can match fields by name, and
allows you to map a source field to multiple destination fields in order to
clone a field.
- Pre-load images on answer side (thanks to Hikaru).
- The `[...]` in cloze deletions is now read as "blank" by TTS (thanks to Rumo).
- The Find&Replace option in the Browse screen can now be used on tags as well.
- Added a Card Info option to the review screen.
- When opening deck option from the study screen, you'll now be asked which deck
you want if the card is in a subdeck.
- You can now choose which add-ons you want to update (thanks to BlueGreenMagick).
- Support system SSL certs on Linux.
- Extra checks are now done when updating a card template, such as detecting when
a cloze notetype is missing a cloze directive, or two templates have identical question sides (thanks to Rumo).
- Support Ctrl+Numpad Enter to add cards.
- Added night mode styling to 'type in the answer' box, and improve legibility
of comparison.
- Sidebar search now scrolls to first match (thanks to Abdo & Rumo).
- F3/F4 in card layout screen go to next/previous template (thanks to Evandro).

Fixes:

- Custom study now limits the tag selection to 100 tags or fewer, to prevent errors caused by exceeding database limits.
- Fixed an issue compiling on recent Python 3.9 installs.
- Fixed audio getting stuck when pausing near end (thanks to kelciour).
- Fixed building on linux-arm64 (thanks to qubist-pixel-ux).
- Fixed Card Info screen not ignoring manual rescheduling when calculating the average time.
- Fixed crash when pressing the copy shortcut with no active selection.
- Fixed current review card sometimes changing when making edits.
- Fixed deck options tooltip appearance (thanks to Matthias).
- Fixed escaping of hyphens in searches (thanks to Rumo).
- Fixed field pin status being forgotten when opening Cards screen (thanks to Henrik).
- Fixed incorrect card count when removing multiple templates.
- Fixed incorrect font on Windows (thanks to Kelciour).
- Fixed resource leak in sound code (thanks to Kelciour).
- Fixed some instances of a flash when revealing answer on cards with images.
- Fixed text with single quote not being escaped in export (thanks to Ryan).
- Fixed various links to the manual (thanks to cherryblossom000).
- Fixed red duplicate background being included in copy+paste (thanks to Hikaru).
- Fixed flags not being excluded on export (thanks to Alex).
- Force x11 mode when the packaged build is run on a system that tells Qt to use
Wayland, as Wayland is not currently supported by the packaged build.
- Numerous behind-the-scenes improvements from Henrik and Rumo.
- Other fixes and improvements, thanks to Abdo, Glutanimate, Arthur, Shaun,
hkr and others.
- Strip invalid unicode from filenames in media check.
- Performance improvements and other miscellaneous fixes.

A big thank you to everyone who contributed, including people who contributed translations,
and those who helped test out the beta releases and provided feedback.

Add-on authors, there are [some notes](https://forums.ankiweb.net/t/add-on-porting-notes-for-anki-2-1-45/11212) on porting add-ons to 2.1.45 available.

- Search text is no longer automatically quoted/interspersed with ANDs.
- Fix two backslashes being treated as one in MathJax.

- The reviewing screen will now wait for up to 100ms
for images to load before showing, and waits until images
have been loaded before scrolling to the answer.
- The default fade-in on the review screen has been removed.
- Fix DB check incorrectly identifying an issue after
lapsing a card with a non-zero interval % in the V1 scheduler.
- Fix editing toolbar being initially active (thanks to Henrik).
- Fix some error messages (thanks to Rumo).
- Fix expand/collapse triggering click in sidebar (thanks to BlueGreenMagick).
- Update translations, thanks to the translators.
- Fix "Forgot Card" message.
- Fix deck list not updating after deleting.

- Fix sync downloads failing when temp folder on separate partition.
- Fix RTL fields (thanks to Abdo).
- Fix issues with field focusing and caret positioning (thanks to Henrik).
- Strip comments when pasting HTML (thanks to Abdo).
- Don't forget CSV delimeter when canceling dialog (thanks to Benjamin).
- Fix stale caches after rolling back to a checkpoint (thanks to Rumo).

Browser improvements:

- Tags now show in a tree (thanks to Abdo).
- Added a search bar to the sidebar (thanks to Abdo).
- New context menu actions to rename or remove tags and their children, rename
decks, manage notetypes, and rename/remove saved searches (thanks to Abdo
and BlueGreenMagick).
- The preview button in the browse screen has moved into the editing area (thanks to Henrik).
- With the improved sidebar, a number of options have been removed from the Filter button.
- The remaining items in the Filter button have been moved into the sidebar, and
the Filter button removed.
- Tags and decks can now be dragged and dropped in the sidebar.
- Each section can now be expanded/collapsed.
- "Due" now shows only cards due that day.
- Added "Overdue" item.
- Click on Decks to show whole collection.
- Click on Flags to show any flag.
- Click on Tags to show all non-empty tags.
- Added "Untagged" under Tags.

Editing improvements:

- `<br>` tags will now be used by default instead of the previous `<div>`
tags, which solves some issues with multiple lines in cloze deletions and
MathJax (thanks to Henrik).
- The tags field in the editor now autocompletes from anywhere in a tag name,
not only the start.
- Invalid field content can no longer spill out into the editing area (thanks to Henrik).

Search improvements:

- Searches are now rewritten into a canonical format (eg `one two` becomes
`"one" AND "two"`) (thanks to Rumo).
- Search error messages are now much more specific (thanks to Rumo).
- is:learn, is:due and prop:due now handle more cases, such as suspended cards
(thanks to Henrik).
- Added prop:pos search to search for new card position (thanks to Abdo).
- Added a shortcut to replace part of a search with a different search
(eg changing the selected deck) (thanks to Rumo).
- Support resched:x for searching for cards that were manually rescheduled
in x days (thanks to Henrik).
- Support prop:rated/resched to search for rated/rescheduled cards over
specific time periods (thanks to Henrik).
- Filtered decks can now be created from a browser search, and vice versa (thanks to Rumo).
- Filtered deck screen now has a link to show cards not matched by search (thanks to Rumo, Abdo).
- Better ergonomics for developers (thanks to Rumo).

Graph improvements:

- A number of the graphs can now be clicked on to search for the cards
displayed by the graph (thanks to Henrik).
- The starting day of week can now be altered in the Calendar graph (thanks to Henrik).
- The Card Counts graph now supports toggling separate suspended/buried counts (thanks to Henrik).
- The intervals and ease graphs now covers more cases, such as suspended cards
(thanks to Henrik).
- Place less emphasis on outliers in the Calendar graph (thanks to Henrik).
- Ignore manually scheduled cards in hour graph.

Scheduler improvements:

- The V2 scheduler no longer applies parent review limits to child decks.
Previously the limits were inconsistently applied, which could lead to the
deck list not reflecting the actual number of cards you'd receive when you
clicked on a deck. AnkiMobile and AnkiWeb have been updated to match this
behaviour, and AnkiDroid will also be updated soon. Using 2.1.41 in
conjunction with older clients will not cause any problems when syncing, but
you may find the deck list/review counts do not match.
- The V1->V2 upgrade process no longer resets cards that are in learning, or
removes cards from filtered decks.
- Users on the old scheduler will now see a message at the top of the deck
list prompting them to update to the Anki 2.1 scheduler.
- There is no option to downgrade to the V1 scheduler anymore, though you can
still do so by downgrading to an older Anki version first.

Reworked the Reschedule tool:

- Split into separate "Forget" and "Set Due Date" actions
- "Set Due Date" defaults to not adjusting the card interval.
- Changed the "Delete Tags" shortcut; Ctrl+Shift+D now changes the due date.
- Added the action to the review screen as well.
- Input now remembered.

Other changes:

- A basic sync server is now built into Anki. It does not yet support
media. Docs are in the docs/ folder of the source tree.
- The title bar on Macs will now turn dark when night mode is activated.
- Deck descriptions of the congratulations screen can be enabled by turning markdown
on in the deck options, but only 2.1.41+ will be able to render the markdown.
- Add opus to media list in editor.
- Edit/More buttons auto-hide when window is small (thanks to Henrik).
- Support Alt+number to switch between clozes in the card layout screen (thanks to Abdo).
- Use monospace font in HTML editor.
- Improve error message when trying to nest under a filtered deck (thanks to Rumo).
- Reposition dialog's "shift cards" option now defaults to off.
- Other fixes and improvements thanks to Henrik, Rumo, Abdo, Arthur, Maksim, Guillem,
stayingpeachy, Daniel, khonkhortisan and Kerrick.

Fixes:

- Fix the Reposition command not preserving the browser sort order.
- Fix some issues causing the sync indicator to show unnecessarily (thanks to Rumo).
- Fix slowdown after large "check media" report.
- Fix a spurious warning about a full sync when renaming card templates.
- Fix a freeze when answering a card with a missing parent deck.
- Fix Anki not working after installing on Linux over a previous install.
- Don't log card resets when exporting.
- Fix congrats screen not showing when learning cards were due soon.
- Updated bundled lame and mpv on Windows and Mac builds.

For developers:

- Add-on authors, please see
<https://forums.ankiweb.net/t/add-on-porting-notes-for-anki-2-1-41/7390>
- Almost all of the Python codebase now has type hints. 🎉
- JS libraries like jQuery have been updated (thanks to Henrik).
- Add (untested) support for ARM64 Linux.
- orjson is turned back into an optional requirement (though is still
recommended, as it's faster).
- The sidebar code has been moved from from browser.py into sidebar.py, which
may break some add-ons.