diff --git a/build-logic/src/main/groovy/org.omegat.document-conventions.gradle b/build-logic/src/main/groovy/org.omegat.document-conventions.gradle
new file mode 100644
index 0000000000..480c895ef8
--- /dev/null
+++ b/build-logic/src/main/groovy/org.omegat.document-conventions.gradle
@@ -0,0 +1,157 @@
+ext {
+    loadProperties = { propFile ->
+        def config = new Properties()
+        if (propFile.canRead()) {
+            propFile.withInputStream { config.load(it) }
+        }
+        config
+    }
+}
+
+tasks.register('manualZips') {
+    description = 'Build ZIP manuals to bundle into application. Requires container runtime.'
+    group = 'documentation'
+}
+
+tasks.register('manualPdfs') {
+    description = 'Build PDF manuals for all languages. Requires container runtime.'
+    group = 'documentation'
+}
+
+tasks.register('manualHtmls') {
+    description = 'Build HTML manuals and zip for all languages. Requires container runtime.'
+    group = 'documentation'
+}
+
+tasks.register('genDocIndex', Copy) {
+    def docPropsFiles = fileTree(dir: 'doc_src', include: '*/version*.properties').findAll {
+        file("${it.parent}/OmegaTUsersManual_xinclude full.xml").file }
+    def langNameExceptions = loadProperties(file('doc_src/lang_exceptions.properties'))
+    def langInfos = docPropsFiles.toSorted{ it.parentFile.name }.collect { props ->
+        def docVersion = loadProperties(props).version
+        ['code': props.parentFile.name, 'nomanual': false, 'version': docVersion,
+         'name': langNameExceptions[props.parentFile.name] ?:
+                 Locale.forLanguageTag(props.parentFile.name.replace('_', '-')).getDisplayName(),
+         'status': docVersion == omtVersion.version ? 'up-to-date' : 'out-of-date'] }
+    def inputTemplate = file('doc_src/index_template.html')
+    def outputIndex = layout.buildDirectory.file("docs/manual/index.html").get().asFile
+    description = 'Generate the docs index file'
+    inputs.files docPropsFiles, inputTemplate
+    outputs.files file(outputIndex)
+    from inputTemplate
+    into outputIndex.parent
+    rename('index_template.html', 'index.html')
+    expand('languages': langInfos)
+    filteringCharset = 'UTF-8'
+    dependsOn manualHtmls
+    group = 'documentation'
+}
+
+tasks.register('webManual', Sync) {
+    group = 'documentation'
+    description = 'Sync the HTML manual files'
+    dependsOn manualHtmls, genDocIndex
+    destinationDir = file(layout.buildDirectory.file("docs/htdocs"))
+    from file(layout.buildDirectory.file("docs/manual"))
+    from('release') {
+        include 'doc-license.txt'
+    }
+}
+
+ext.manualIndexXmls = fileTree(dir: 'doc_src', include: '**/OmegaTUsersManual_xinclude full.xml')
+manualIndexXmls.each { xml ->
+    def lang = xml.parentFile.name
+    def pdfTaskName = "manualPdf${lang.capitalize()}"
+    tasks.register(pdfTaskName, Exec) {
+        inputs.files fileTree(dir: "doc_src/${lang}", includes: ['**/*.xml', 'images/*.png'],
+                excludes: ['xhtml5/*', 'index.xml'])
+        outputs.files layout.buildDirectory.file("docs/pdfs/OmegaT_documentation_${lang}.PDF")
+        onlyIf {
+            conditions([exePresent('docker') || exePresent('nerdctl'), 'Docker or nerdctl is not installed'],
+                    [!project.hasProperty('forceSkipDocumentBuild'), 'Specified forceSkipDocumentBuild property'])
+        }
+        workingDir = 'doc_src'
+        commandLine './docgen', "-Dlanguage=${lang}", "-Dtarget=../build/docs/pdfs", 'pdf'
+        doLast {
+            delete fileTree(dir: "doc_src/${lang}", includes: ['pdf/*', 'index.xml'])
+        }
+    }
+    manualPdfs.dependsOn pdfTaskName
+
+    def htmlTaskName = "manualHtml${lang.capitalize()}"
+    tasks.register(htmlTaskName, Exec) {
+        inputs.files fileTree(dir: "doc_src/${lang}", includes: ['**/*.xml', 'images/*.png'],
+                excludes: ['xhtml5/*', 'index.xml'])
+        outputs.files fileTree(dir: layout.buildDirectory.file("docs/manual/${lang}/"),
+                includes: ['*.html', 'OmegaT.css', 'images/*.png', '_wh/**/*.js', '_wh/wh.css'])
+        onlyIf {
+            conditions([exePresent('docker') || exePresent('nerdctl'), 'Docker or nerdctl is not installed'],
+                    [!project.hasProperty('forceSkipDocumentBuild'), 'Specified forceSkipDocumentBuild property'])
+        }
+        workingDir = 'doc_src'
+        commandLine './docgen', "-Dlanguage=${lang}", "-Dtarget=../build/docs/manual/${lang}", 'html5'
+    }
+    manualHtmls.dependsOn htmlTaskName
+
+    def zipTaskName="manualZip${lang.capitalize()}"
+    def versionProperties = loadProperties(file("doc_src/${lang}/version_${lang}.properties"))
+    if (lang.equals("en") || versionProperties.version.equals(omtVersion.version)) {
+        tasks.register(zipTaskName, Zip) {
+            from fileTree(dir: layout.buildDirectory.file("docs/manual/${lang}"))
+            exclude 'docs/manual/index.html'
+            from fileTree(dir: "doc_src/${lang}", include: '**/version*.properties')
+            archiveFileName = "${lang}.zip"
+            destinationDirectory = file("${buildDir}/docs/manuals/")
+        }
+        manualZips.dependsOn zipTaskName
+        tasks.getByName(zipTaskName).dependsOn htmlTaskName
+    }
+}
+
+tasks.register('firstSteps') {
+    description = 'Build First pages for all languages at docs/greetings/. Requires Docker.'
+    group = 'documentation'
+}
+
+tasks.register('updateManuals') {
+    group = 'documentation'
+    description = 'Update Instant Start guides and HTML manuals.'
+    dependsOn manualHtmls, firstSteps, genDocIndex
+}
+
+ext.firstStepsXmls = fileTree(dir: 'doc_src', include: '**/First_Steps.xml')
+firstStepsXmls.each { xml ->
+    def lang = xml.parentFile.name
+    def taskName = "firstSteps${lang.capitalize()}"
+    tasks.register(taskName, Exec) {
+        inputs.files fileTree(dir: "doc_src/${lang}", include: 'First_Steps.xml')
+        outputs.files fileTree(dir: layout.buildDirectory.file('docs/greetings/'),
+                includes: ["${lang}/first_steps.html", "${lang}/OmegaT.css"])
+        onlyIf {
+            conditions([exePresent('docker') || exePresent('nerdctl'), 'Docker or nerdctl is not installed'],
+                    [!project.hasProperty('forceSkipDocumentBuild'), 'Specified forceSkipDocumentBuild property'])
+        }
+        workingDir = 'doc_src'
+        commandLine './docgen', "-Dlanguage=${lang}", "-Dtarget=../build/docs/greetings/${lang}", 'first-steps'
+    }
+
+    firstSteps.dependsOn taskName
+}
+
+ext.instantStartXmls = fileTree(dir: 'doc_src', include: '**/InstantStartGuide.xml')
+instantStartXmls.each { xml ->
+    def lang = xml.parentFile.name
+    def taskName = "instantStartGuide${lang.capitalize()}"
+    tasks.register(taskName, Exec) {
+        inputs.files fileTree(dir: "doc_src/${lang}", includes: ['InstantStartGuide.xml', '**/InstantGuide*png'])
+        outputs.files fileTree(dir: layout.buildDirectory.file('docs/greetings/'),
+                includes: ["${lang}/first_steps.html", "${lang}/images/InstantGuide*png", "${lang}/OmegaT.css"])
+        onlyIf {
+            conditions([exePresent('docker') || exePresent('nerdctl'), 'Docker or nerdctl is not installed'],
+                    [!project.hasProperty('forceSkipDocumentBuild'), 'Specified forceSkipDocumentBuild property'])
+        }
+        workingDir = 'doc_src'
+        commandLine './docgen', "-Dlanguage=${lang}", "-Dtarget=../build/docs/greetings/${lang}", 'instant-start'
+    }
+    firstSteps.dependsOn taskName
+}
diff --git a/build.gradle b/build.gradle
index a736e85992..f45ad046cc 100644
--- a/build.gradle
+++ b/build.gradle
@@ -5,6 +5,7 @@ import java.nio.file.Paths
 plugins {
     id 'org.omegat.java-conventions'
     id 'org.omegat.java-jaxb-generate'
+    id 'org.omegat.document-conventions'
     id 'application'
     id 'java-test-fixtures'
     id 'maven-publish'
@@ -334,154 +335,6 @@ launch4j {
     priority = 'normal'
 }
 
-tasks.register('manualZips') {
-    description = 'Build ZIP manuals to bundle into application. Requires container runtime.'
-    group = 'documentation'
-}
-
-tasks.register('manualPdfs') {
-    description = 'Build PDF manuals for all languages. Requires container runtime.'
-    group = 'documentation'
-}
-
-tasks.register('manualHtmls') {
-    description = 'Build HTML manuals and zip for all languages. Requires container runtime.'
-    group = 'documentation'
-}
-
-tasks.register('genDocIndex', Copy) {
-    def docPropsFiles = fileTree(dir: 'doc_src', include: '*/version*.properties').findAll {
-        file("${it.parent}/OmegaTUsersManual_xinclude full.xml").file }
-    def langNameExceptions = loadProperties(file('doc_src/lang_exceptions.properties'))
-    def langInfos = docPropsFiles.toSorted{ it.parentFile.name }.collect { props ->
-        def docVersion = loadProperties(props).version
-        ['code': props.parentFile.name, 'nomanual': false, 'version': docVersion,
-         'name': langNameExceptions[props.parentFile.name] ?:
-                 Locale.forLanguageTag(props.parentFile.name.replace('_', '-')).getDisplayName(),
-         'status': docVersion == omtVersion.version ? 'up-to-date' : 'out-of-date'] }
-    def inputTemplate = file('doc_src/index_template.html')
-    def outputIndex = layout.buildDirectory.file("docs/manual/index.html").get().asFile
-    description = 'Generate the docs index file'
-    inputs.files docPropsFiles, inputTemplate
-    outputs.files file(outputIndex)
-    from inputTemplate
-    into outputIndex.parent
-    rename('index_template.html', 'index.html')
-    expand('languages': langInfos)
-    filteringCharset = 'UTF-8'
-    dependsOn manualHtmls
-    group = 'documentation'
-}
-
-tasks.register('webManual', Sync) {
-    group = 'documentation'
-    description = 'Sync the HTML manual files'
-    dependsOn manualHtmls, genDocIndex
-    destinationDir = file(layout.buildDirectory.file("docs/htdocs"))
-    from file(layout.buildDirectory.file("docs/manual"))
-    from('release') {
-        include 'doc-license.txt'
-    }
-}
-
-ext.manualIndexXmls = fileTree(dir: 'doc_src', include: '**/OmegaTUsersManual_xinclude full.xml')
-manualIndexXmls.each { xml ->
-    def lang = xml.parentFile.name
-    def pdfTaskName = "manualPdf${lang.capitalize()}"
-    tasks.register(pdfTaskName, Exec) {
-        inputs.files fileTree(dir: "doc_src/${lang}", includes: ['**/*.xml', 'images/*.png'],
-                excludes: ['xhtml5/*', 'index.xml'])
-        outputs.files layout.buildDirectory.file("docs/pdfs/OmegaT_documentation_${lang}.PDF")
-        onlyIf {
-            conditions([exePresent('docker') || exePresent('nerdctl'), 'Docker or nerdctl is not installed'],
-                    [!project.hasProperty('forceSkipDocumentBuild'), 'Specified forceSkipDocumentBuild property'])
-        }
-        workingDir = 'doc_src'
-        commandLine './docgen', "-Dlanguage=${lang}", "-Dtarget=../build/docs/pdfs", 'pdf'
-        doLast {
-            delete fileTree(dir: "doc_src/${lang}", includes: ['pdf/*', 'index.xml'])
-        }
-    }
-    manualPdfs.dependsOn pdfTaskName
-
-    def htmlTaskName = "manualHtml${lang.capitalize()}"
-    tasks.register(htmlTaskName, Exec) {
-        inputs.files fileTree(dir: "doc_src/${lang}", includes: ['**/*.xml', 'images/*.png'],
-                excludes: ['xhtml5/*', 'index.xml'])
-        outputs.files fileTree(dir: layout.buildDirectory.file("docs/manual/${lang}/"),
-                includes: ['*.html', 'OmegaT.css', 'images/*.png', '_wh/**/*.js', '_wh/wh.css'])
-        onlyIf {
-            conditions([exePresent('docker') || exePresent('nerdctl'), 'Docker or nerdctl is not installed'],
-                [!project.hasProperty('forceSkipDocumentBuild'), 'Specified forceSkipDocumentBuild property'])
-        }
-        workingDir = 'doc_src'
-        commandLine './docgen', "-Dlanguage=${lang}", "-Dtarget=../build/docs/manual/${lang}", 'html5'
-    }
-    manualHtmls.dependsOn htmlTaskName
-
-    def zipTaskName="manualZip${lang.capitalize()}"
-    def versionProperties = loadProperties(file("doc_src/${lang}/version_${lang}.properties"))
-    if (lang.equals("en") || versionProperties.version.equals(omtVersion.version)) {
-        tasks.register(zipTaskName, Zip) {
-            from fileTree(dir: layout.buildDirectory.file("docs/manual/${lang}"))
-            exclude 'docs/manual/index.html'
-            from fileTree(dir: "doc_src/${lang}", include: '**/version*.properties')
-            archiveFileName = "${lang}.zip"
-            destinationDirectory = file("${buildDir}/docs/manuals/")
-        }
-        manualZips.dependsOn zipTaskName
-        tasks.getByName(zipTaskName).dependsOn htmlTaskName
-    }
-}
-
-tasks.register('firstSteps') {
-    description = 'Build First pages for all languages at docs/greetings/. Requires Docker.'
-    group = 'documentation'
-}
-
-tasks.register('updateManuals') {
-    group = 'documentation'
-    description = 'Update Instant Start guides and HTML manuals.'
-    dependsOn manualHtmls, firstSteps, genDocIndex
-}
-
-ext.firstStepsXmls = fileTree(dir: 'doc_src', include: '**/First_Steps.xml')
-firstStepsXmls.each { xml ->
-    def lang = xml.parentFile.name
-    def taskName = "firstSteps${lang.capitalize()}"
-    tasks.register(taskName, Exec) {
-        inputs.files fileTree(dir: "doc_src/${lang}", include: 'First_Steps.xml')
-        outputs.files fileTree(dir: layout.buildDirectory.file('docs/greetings/'),
-                includes: ["${lang}/first_steps.html", "${lang}/OmegaT.css"])
-        onlyIf {
-            conditions([exePresent('docker') || exePresent('nerdctl'), 'Docker or nerdctl is not installed'],
-                    [!project.hasProperty('forceSkipDocumentBuild'), 'Specified forceSkipDocumentBuild property'])
-        }
-        workingDir = 'doc_src'
-        commandLine './docgen', "-Dlanguage=${lang}", "-Dtarget=../build/docs/greetings/${lang}", 'first-steps'
-    }
-
-    firstSteps.dependsOn taskName
-}
-
-ext.instantStartXmls = fileTree(dir: 'doc_src', include: '**/InstantStartGuide.xml')
-instantStartXmls.each { xml ->
-    def lang = xml.parentFile.name
-    def taskName = "instantStartGuide${lang.capitalize()}"
-    tasks.register(taskName, Exec) {
-        inputs.files fileTree(dir: "doc_src/${lang}", includes: ['InstantStartGuide.xml', '**/InstantGuide*png'])
-        outputs.files fileTree(dir: layout.buildDirectory.file('docs/greetings/'),
-                includes: ["${lang}/first_steps.html", "${lang}/images/InstantGuide*png", "${lang}/OmegaT.css"])
-        onlyIf {
-            conditions([exePresent('docker') || exePresent('nerdctl'), 'Docker or nerdctl is not installed'],
-                    [!project.hasProperty('forceSkipDocumentBuild'), 'Specified forceSkipDocumentBuild property'])
-        }
-        workingDir = 'doc_src'
-        commandLine './docgen', "-Dlanguage=${lang}", "-Dtarget=../build/docs/greetings/${lang}", 'instant-start'
-    }
-    firstSteps.dependsOn taskName
-}
-
 tasks.register('genMac') {
     def appbundlerClasspath = configurations.genMac.asPath
     def outDir = layout.buildDirectory.file("appbundler").get().toString()