thunderbird: Update to 78.2.1

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Changelog:
78.2.1
Changes
changed OpenPGP enabled by default
changed OpenPGP: Disabled the use of MD5/SM2/SM3 algorithms

Fixes
fixed OpenPGP: Users with sub-identities were unable to encrypt or sign messages when switching identities
fixed OpenPGP message security window did not support dark mode

78.2.0
Changes
changed OpenPGP Key generation now disabled when there is no default mail account configured
changed OpenPGP: Encrypt saved drafts when OpenPGP is enabled
changed Twitter search removed
changed Calendar: Event summary dialog is now themeable
changed MailExtensions: Some APIs now use defineLazyPreferenceGetter in order to benefit from caching

Fixes
fixed OpenPGP Key Manager search function did not work
fixed OpenPGP Key Properties dialog was sometimes too small
fixed OpenPGP: Encrypted email would not send if address contained uppercase characters
fixed OpenPGP: "Key ID" column could not be resized in Key Manage
fixed OpenPGP: Keys containing invalid UTF-8 strings could not be imported
fixed OpenPGP: Enable automatic signing for encrypted messages in additional scenarios
fixed Many more OpenPGP bug fixes and improvements
fixed IMAP fetch chunk size was always 65536 bytes
fixed IMAP server capabilities were not rechecked after upgrading to SSL/TLS connection
fixed Message Composer: Order of attachments could not be modified using drag & drop
fixed Composing messages with a "fixed width" font did not work
fixed Drag and drop of address book contacts did not work in some situations
fixed Address book migration failed when there was a dot in the file name
fixed Address book: "Always prefer display name over message header" was always checked when editing a contact
fixed Address book performance optimizations
fixed Dialog to add a new mail account from "Account Settings" did not open
fixed "Select All" (Ctrl+A) in message source did not work until focused with a mouse click
fixed Ctrl+scroll wheel not zooming in message reader
fixed Setting/changing a signature from a file lost when closing account settings
fixed Adaptive Junk Mail settings could not be disabled
fixed Message filter dialog fixes: Missing scrollbar, drop-down list not wide enough
fixed Various UX and theme improvements

78.1.1
Changes
changed Building OpenPGP shared library linked to system libraries now supported
changed MailExtension errors now shown in Developer Tools console by default
changed MailExtensions: Dynamic registration of calendar providers now supported

Fixesr
fixed OpenPGP improvements
fixed Message preview was sometimes blank after upgrading from Thunderbird 68
fixed Email addresses whitelisted for remote content not displayed in preferences
fixed Importing data from Seamonkey did not work
fixed Renaming a mail list did not update the side bar
fixed MailExtensions: messenger.* namespace was undefined

78.1.0
What's New
new OpenPGP support is now feature complete. Improvements: new Key Wizard, online searching for OpenPGP keys, and more
new The preferences tab now has a search field

Changes
changed Dark background in message reader is now disabled

Fixes
fixed Thunderbird startup was slow when using folder color customizations with many folders. Previously configured colors will not be migrated.
fixed Mail quota usage in status bar did not support terabyte folder sizes
fixed Changing Junk mail settings with keyboard toggled wrong setting
fixed Advanced IMAP server preferences not saved in Account Manager
fixed Address book migration updates and fixes
fixed Address book: Last Modified Date was not updated
fixed Dark mode improvements
fixed Various security fixes

Security fixes:
#CVE-2020-15652: Potential leak of redirect targets when loading scripts in a worker
#CVE-2020-6514: WebRTC data channel leaks internal address to peer
#CVE-2020-15655: Extension APIs could be used to bypass Same-Origin Policy
#CVE-2020-15653: Bypassing iframe sandbox when allowing popups
#CVE-2020-6463: Use-after-free in ANGLE gl::Texture::onUnbindAsSamplerTexture
#CVE-2020-15656: Type confusion for special arguments in IonMonkey
#CVE-2020-15658: Overriding file type when saving to disk
#CVE-2020-15657: DLL hijacking due to incorrect loading path
#CVE-2020-15654: Custom cursor can overlay user interface
#CVE-2020-15659: Memory safety bugs fixed in Thunderbird 78.1

78.0.1
What's New
new OpenPGP: Key revocation, extending key expiration, and secret key backup

Fixes
fixed Drag & Drop multiple attachments to macOS Finder created duplicate files
fixed Faceted search date and relevance settings not saved
fixed FileLink attachments included as a link and file when added from a network drive via drag & drop
fixed About Thunderbird dialog keyboard shortcuts did not work
fixed CC'd recipients sometimes displayed collapsed in header pane
fixed Incremental search in contacts sidebar did not always display local results when an LDAP server was also in use
fixed Contacts sidebar search results cleared after removing a contact
fixed OpenPGP: Messages with long Armor Header lines did not display
fixed OpenPGP: Messages containing non-UTF-8 text were not supported
fixed Various UI and theming fixes
fixed Chat: Participants list did not display operator flags

(ryoon)