(fixed up this run-on paragraph) Thunderbird has upgrade from version 60.9 (32 bits) to version 68.1 (64 bits) but in this process, under Windows 7 x64 SP1, the program is working in worst conditions. * When start (running Thunderbird from Icon Desktop), the calendar don´t appeared until some accounts checking occurred (and sometimes does not appear at all and I have to close the app and run it again or access to the calendar pane), * the calendar show its information with some delay (is less faster than the previous version), * some add-ons (like Card Book) don´t work fine (the address book data appear and disappear). I have been using Thunderbird since many years ago, and I wish to thanks all the efforts to give us a free and good software, but the version 68,1 has worsened the reliable previous (60.9) versions and I hope this issues can be solved in future releases. I have reinstall the program, importing the messages bases, accounts, etc., but the 68.1 version is still less reliable than 60.9. In the Add-ons Control Panel the add-ons, first, show quickly an advert, and later on (less than two seconds) are recognized correctly. Here are pert of the Error logs: XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. messenger.xul WebExtensions: Loading packed extension from C:\Users\admin\AppData\Roaming\Thunderbird\Profiles\\{e2fda1a4-762b-4020-b5ad-a41df1933103}.xpi ext-legacy.js:109 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:13 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:14 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:15 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:16 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:17 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:18 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:19 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:20 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:21 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:22 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:23 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:24 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:25 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:26 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:27 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:28 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:29 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:30 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:31 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:32 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:33 Ignoring unrecognized chrome manifest directive 'style'. chrome.manifest:38 Ignoring unrecognized chrome manifest directive 'style'. chrome.manifest:39 Ignoring unrecognized chrome manifest directive 'style'. chrome.manifest:40 Ignoring unrecognized chrome manifest directive 'style'. chrome.manifest:41 Ignoring unrecognized chrome manifest directive 'style'. chrome.manifest:42 Ignoring unrecognized chrome manifest directive 'style'. chrome.manifest:43 Ignoring unrecognized chrome manifest directive 'style'. chrome.manifest:44 Ignoring unrecognized chrome manifest directive 'style'. chrome.manifest:45 Ignoring unrecognized chrome manifest directive 'style'. chrome.manifest:46 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:7 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:9 WebExtensions: Loading packed extension from C:\Users\admin\AppData\Roaming\Thunderbird\Profiles\\extensions\ImportExportToolsNG@cleidigh.kokkini.net.xpi ext-legacy.js:109 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:10 Ignoring unrecognized chrome manifest directive 'overlay'. chrome.manifest:11 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. 2 folderDisplay.js:2491:9 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. 3 messenger.xul WebExtensions: Loading add-on preferences from C:\Users\admin\AppData\Roaming\Thunderbird\Profiles\\extensions\ImportExportToolsNG@cleidigh.kokkini.net.xpi ext-legacy.js:142 WebExtensions: Firing profile-after-change listeners for ImportExportToolsNG@cleidigh.kokkini.net ext-legacy.js:146 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. messenger.xul WebExtensions: Loading add-on preferences from C:\Users\admin\AppData\Roaming\Thunderbird\Profiles\\extensions\{e2fda1a4-762b-4020-b5ad-a41df1933103}.xpi ext-legacy.js:142 WebExtensions: Firing profile-after-change listeners for {e2fda1a4-762b-4020-b5ad-a41df1933103} ext-legacy.js:146 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. messenger.xul Use of Mutation Events is deprecated. Use MutationObserver instead. calendar-views.js:96:17 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. messenger.xul XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. calendar-base-view.js:709:41 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. 41 messenger.xul XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. 2 folderDisplay.js:2491:9 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. 4 messenger.xul XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. mailWidgets.js:884:27 Successfully compiled asm.js code (total compilation time 6ms) openpgp-lib.jsm Successfully compiled asm.js code (total compilation time 11ms) openpgp-lib.jsm Successfully compiled asm.js code (total compilation time 95ms) openpgp-lib.jsm XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. 2 messenger.xul XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. mailWidgets.js:884:27 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. 2 messenger.xul XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. mailWidgets.js:884:27 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. messenger.xul XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. folderDisplay.js:939:6 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. 2 folderDisplay.js:2491:9 XUL box for statusbarpanel element contained an inline #text child, forcing all its children to be wrapped in a block. 2 messenger.xul NS_ERROR_ABORT: Certificate issuer is not built-in. CertUtils.jsm:182 Stylesheets without CSSOM changes reparsed to check for errors. Refresh the page to also see errors from stylesheets changed from CSSOM and from style attributes. 13 Unknown property ‘user-select’. Declaration dropped. reps.css:23:15 Stylesheets without CSSOM changes reparsed to check for errors. Refresh the page to also see errors from stylesheets changed from CSSOM and from style attributes. Thanks