Set Qt::AA_EnableHighDpiScaling application attribute when Qt 5.14.x or
newer is used. This fixes a lot of scaling issues on HiDPI displays.
Unfortunately, this flag must be set only before QApllication object
creation, so the only one place where it can be done is main().
* Fix wrong fields for translation comments
* Improve torrent management tooltip to cover both modes
* Add new tooltips for potentially confusing settings
Decent progress towards #6346, closes#9994, closes#11528
BEP-3 says all tracker responses to valid announce requests should be bencoded dictionaries with at least the "peers" and "interval" keys; the "peers" key can be empty.
Also clarify support for BEP-21.
The embedded tracker was returning a non-compliant response.
The peer lists should be packed strings instead of lists.
Also clarify level of compliance with BEP-7.
The `comment` field is used for disambiguation between identical
strings. Our case here should use the `extracomment` field which
meant as comment for translators.
`/api/v2/torrents/info` can now take the following new values for the`filter` parameter: `stalled`, `stalled_uploading` and `stalled_downloading`.
Requires Web API version bump.
Closes#11787
Filter list (left side panel) in WebUI is implemented using <a> tags,
CSS defines default style for all <a> elements, and specific style for
filter list elements. Default style for <a> elements sets color, and
this color also used in list. This is looks not so well. So lets just
inherit text color from parent element, and as so as it is not set, so
default text color will be used.
This makes filter list looks like other UI elemets, making all UI more
consistent (like in desktop app).
1. Use unified function names `initInstance()` and `freeInstance()` and
make them public.
2. Add `freeInstance()` to avoid noise from memory leak detectors.
3. Let `instance()`return a pointer directly to avoid unnecessary
indirections when invoking functions.
