* A new feature allows to reset automatically any counter (global, independant) at periodic time: each day/week/month/year.

* Format and update settings for independant counters can now be defined independantly for each counter.

* A new metadata which allows to insert the week number has been added: %V/%v.

* The computation mechanism of modifiers has been improved and enhanced so that the usage of spreading metadata (uppercase versions) cannot get incorrect dates (e.g.: February, the 30th!).

* bugfix: If no default subjects was set then the addon update did not complete thus leaving the addon with undefined values which may lead to unpredictable behaviour and crash (addon and/or TB) (bug introduced in v0.5.0).

* Several metadata have changed (eg. minutes count '%n' replaces '%m', '%j' replaces '%s', etc.). Existing subjects (list, defaults, filters) have been updated with the new metadata version.

* Metadata can now be precised with a numerical modifier to add/subtract the modifier value to the related metadata. This allows to calculate yesterday, last month, next year, etc.

* Subjects can now be exported to and imported from file.

* The addon is now compatible with Thunderbird from v59.* to v60.*.

* The addon has been upgraded so that it passes the v58/v59/v60 TB barriers (previous version was only really compatible with TV <= v57).

* Due do its long-time stability and the absence of requests for new realistic features or upgrades, the addon versioning has been moved to v1.x.

* Debug messages are now timestamped with local time.

* A new debug option allows to export settings in a file, allowing to send it to support contact.

* Maximum compatibility setting has been enabled for Thunderbird v56.* to v59.0.

* The addon has been upgraded so that it passes the "v57" TB barrier.

* Filters which are disabled are now displayed in italic in settings dialog.

* Filters tab in settings dialog offers now a help button to describe the feature.

* Filters subjects feature offers a new metadata to insert the subject of the received message: %S (described in the help button). This metadata is only handled for filters subjects.

* bugfix: For filters subjects, in some cases the detection of the identity of the recipient for the received message did not work.

* bugfix: If case-sensitive was disabled and a subject was modified with only changes about case-sensitivity then changes could not be saved.

* Maximum compatibility setting has been enabled for Thunderbird v52.* to v56.0.

* The addon handles now message filters. It can replace subject of template messages sent as replies.

* In settings dialog, if 'advanced mode' is enabled, then a simulation of the selected/modified subject is displayed.

* In settings dialog, default subject can now be picked in a list containing all subjects of the main list. It is still possible to set a subject which is not one from the list.

* Behaviour of interactive settings dialog has been enhanced.

* Maximum compatibility setting has been enabled for Thunderbird v45.* to v52.0.

* Detection mechanism of native 'Subject' label has been enhanced.

* Some code snippets have been optimized.

* bugfix: The addon was in conflict with another addon ("mrc compose"). When opening compose dialog the initialization crashed.

* Each account can now have a distinct default subject with distinct parameters.

* Settings for identities' account are now displayed in italics in individual counters list.

* It is now possible to update current subject which was previously inserted during the same composing session, thus updating special values such as time and date values.

* If 'focus email body once a subject has been picked' is not checked then default behaviour is to return focus to subject field.

* bugfix: Counter values for identities' accounts were not handled properly (inserted value was always '1').

* bugfix: For TB >= v38 individual counters values were not handled properly and value was always '1'.

* bugfix: Some settings changes in settings dialog were not activated until TB was restarted.

* bugfix: Default subjects containing non-ASCII characters were not handled correctly.

* Maximum compatibility setting has been enabled for Thunderbird v38.* to v45.0.

* bugfix: For TB >= v31.*, picking a subjet from the autocompletion drop-down list no longer adds it to the subject field (thanks to Gavin Coles).

* bugfix: If global counter was set to be updated when any individual counter was updated, as when saving and/or sending, then global counter was updated twice (=incremented by 2 instead of 1).

* bugfix: When clicking 'reset to factory default' button, final message advising to restart TB wasn't displayed.

* Maximum compatibility setting has been enabled for Thunderbird v26.* to v38.0.

* The addon allows now to log debug information directly into a user-defined file.

* bugfix: When installing or upgrading the addon on MacOS systems with Gloom not installed, no information popup dialog was displayed and the addon crashed.

* Maximum compatibility setting has been enabled for Thunderbird v21.* to v26.0.

* Identity counters are now displayed in a way they can be easily recognised from accounts in 'counters' tab.

* The 're-initialize auto-completion' is not displayed anymore for TB >= v5.* because it is only useful for prior versions.

* The addon is now compatible with Thunderbird starting from v20.*.

* Maximum compatibility setting has been enabled for Thunderbird v20.* to v21.0a1.

* An option has been added which allows to skip insertion of default subject if subject is not previously empty. Hence default subject is not added to a previously-saved message which is re-opened.

* Inner counter meta-data has been modified: it has been turned into a 'global' inner counter and metadata has changed from '%c' to '%g'.

* Advanced mode offers now 3 meta-data: each account can have a dedicated inner counter which is incremented each time it is used ('%i'), hours on a 12-hours clock format ('%k'), and 'AM/PM' information ('%p').

* Individual counters can now handle distinct counters for each unique identity of a same account.

* Settings dialog offers now a GUI to handle counters meta-data: user can change values and set when counters are updated.

* Maximum compatibility setting has been enabled for Thunderbird v16.* to v19.0a1.

* Advanced mode offers now another meta-data: an inner counter which is incremented each time it is used.

* bugfix: Automatic prefixes lists containing non-ASCII characters were not handled correctly.

* Maximum compatibility setting has been enabled for Thunderbird v12.* to v16.0a1.

* It's now possible to set a replacement string for native automatic 'reply' and 'transfert' prefixes. This replacement is performed only for first automatic prefix kept when removing automatic prefixes.

* 'Automatic prefixes' tab page from settings dialog has been redesigned.

* Alert dialog when installing or upgrading addon has been replaced by a popup dialog.

* bugfix: Default subjects containing non-ASCII characters were not handled correctly.

* Subjects management offers now an advanced mode: subjects can contain some meta-data like current_date, current_time, or such which are parsed when subject is inserted into subject field.

* A default subject can now be set to be automatically inserted as soon as compose dialog is opened.

* bugfix: Insertion point was not resetted between composing sessions, thus resulting in unpredictable behaviour when inserting a subject using one of these 2 modes:
- append to the beginning of current subject + append to the end of previous picked subject
- append to the end of current subject + append to the beginning of previous picked subject

* Maximum compatibility setting has been enabled for Thunderbird v10.* to v12.0a1.

* An option has been added to select automatically email body once a subject has been picked (thanks to Jeff). This option can be enabled or disabled from options dialog.

* Autocompletion can now be case-sensitive or case-insensitive (thanks to Vinser). This option can be chosen in settings dialog.

* Subjects management (add, sort, etc.) can now be case-sensitive or case-insensitive. This option can be chosen in settings dialog.

* A button has been added in settings dialog to clean and reset all settings to factory defaults (useful when upgrading addon version to delete obsolete parameters or to reinitialize all settings).

* When adding a subject in settings dialog, listbox is set so that new subject is visible.

* In settings dialog, new subject textbox is now spellcheck-compatible.

* In settings dialog, 'Add' and 'Remove' subject buttons have no more label but icon. 'Sort' icon has been changed.

* Toolbar button icon is now greyed-out when button is disabled.

* The way subject textbox is handled when autocompletion is disabled has been improved to make it the closest possible to native behaviour.

* Subject textbox autocompletion has been enhanced to reduce conflict with other potential autocompletion modules.

* Subjects list setting has been enhanced to optimize stability.

* Russian translation has been added (thanks to Vinser).

* Swedish translation has been added (thanks to Mikael Hiort af Ornäs).

* bugfix: Adding a subject which was exactly a piece of an already existing subject was considered as adding the same subject twice, then subject was not added to subjects list.

* bugfix: Autocompletion crashed when adding a subject containing special characters (ex.: double-quote) (thanks to Vinser).

* bugfix: Subjects list and autocompletion array were not updated when adding a subject through custom 'Subjects' button until subjects list was displayed again.

* bugfix: When updating addon a second custom toolbar button was added to toolbar even if a previous custom one was already displayed, thus 2 toolbar buttons were displayed (for TB v2 only).

* bugfix: Compose dialog title bar was not updated when picking a subject from the list.

* bugfix: In certain circumstances, subjects list was corrupted when resetting settings.

* bugfix: With a subjects list containing 10 subjects or more, picking a subject with an index higher or equal than 10 filled subject textbox with a wrong subject.

* The addon is now compatible with Thunderbird v3.* to v9.*.

* In options dialog sort of predefined subjects has been changed. Now a natural sort is used.

* A minimum height of native subject textbox has been set. Thus, it is not too narrow when auto-completion is enabled (nb: this depends on the used theme; for many themes this won't be a visible change (e.g: native Linux theme)).