Add rider/idea to gitignore

.gitignore

@@ -138,7 +138,7 @@ publish/
 # Publish Web Output
 *.[Pp]ublish.xml
 *.azurePubxml
-# TODO: Comment the next line if you want to checkin your web deploy settings 
+# TODO: Comment the next line if you want to checkin your web deploy settings
 # but database connection strings (with potential passwords) will be unencrypted
 *.pubxml
 *.publishproj
@@ -216,3 +216,26 @@ FakesAssemblies/
 **/*.Server/GeneratedArtifacts
 **/*.Server/ModelManifest.xml
 _Pvt_Extensions
+
+# Common IntelliJ Platform excludes
+
+# User specific
+**/.idea/**/workspace.xml
+**/.idea/**/tasks.xml
+**/.idea/shelf/*
+**/.idea/dictionaries
+**/.idea/httpRequests/
+
+# Sensitive or high-churn files
+**/.idea/**/dataSources/
+**/.idea/**/dataSources.ids
+**/.idea/**/dataSources.xml
+**/.idea/**/dataSources.local.xml
+**/.idea/**/sqlDataSources.xml
+**/.idea/**/dynamic.xml
+
+# Rider
+# Rider auto-generates .iml files, and contentModel.xml
+**/.idea/**/*.iml
+**/.idea/**/contentModel.xml
+**/.idea/**/modules.xml

src/markdig.sln

@@ -9,6 +9,9 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Build", "Build", "{061866E2
 		..\.github\workflows\ci.yml = ..\.github\workflows\ci.yml
 		..\license.txt = ..\license.txt
 		..\readme.md = ..\readme.md
+		..\.editorconfig = ..\.editorconfig
+		..\.gitattributes = ..\.gitattributes
+		..\.gitignore = ..\.gitignore
 	EndProjectSection
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Markdig", "Markdig\Markdig.csproj", "{8A58A7E2-627C-4F41-933F-5AC92ADFAB48}"