diff --git a/manifests/Mozilla/Thunderbird/Thunderbird_v78.1.0/78.1.0 (SI).yaml b/manifests/Mozilla/Thunderbird/Thunderbird_v78.1.0/78.1.0 (SI).yaml
new file mode 100644
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+++ b/manifests/Mozilla/Thunderbird/Thunderbird_v78.1.0/78.1.0 (SI).yaml	
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+Id: Mozilla.Thunderbird.Thunderbird_v78.1.0
+Version: 78.1.0 (SI)
+Name: Thunderbird (Sinhalese)
+Publisher: Mozilla
+License: Mozilla Public License Version 2.0
+LicenseUrl: https://www.mozilla.org/en-US/MPL/2.0/
+AppMoniker: thunderbird, Thunderbird (Sinhalese)
+Tags: thunderbird, Thunderbird (Sinhalese), email, E-mail
+Description: Thunderbird is a free email application that’s easy to set up and customize!
+Homepage: https://www.thunderbird.net
+Installers:
+  - Arch: x64
+    Url: https://download-installer.cdn.mozilla.net/pub/thunderbird/releases/78.1.0/win64/si/Thunderbird%20Setup%2078.1.0.msi
+    Sha256: A8F74C4125D37CC99B15120E734158D4B6D68778027B53123653EC6D8DAF36D9
+    InstallerType: msi