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Co-authored-by: per1234 <[email protected]>

Author: cmaglie

Diff for: docs/UPGRADING.md

@@ -13,10 +13,10 @@ We also started using a linter to implement checks for gRPC API style errors.
 
 This provides a better consistency and higher quality API but inevitably introduces breaking changes.
 
-### gRPC API breaking changes
+#### gRPC API breaking changes
 
 Consumers of the gRPC API should regenerate their bindings and update all structures naming where necessary. Most of the
-changes are trivial and falls into the following categories:
+changes are trivial and fall into the following categories:
 
 - Service names have been suffixed with `...Service` (for example `ArduinoCore` -> `ArduinoCoreService`)
 - Message names suffix has been changed from `...Req`/`...Resp` to `...Request`/`...Response` (for example
@@ -28,7 +28,7 @@ changes are trivial and falls into the following categories:
 - Package names are now versioned (for example `cc.arduino.cli.commands` -> `cc.arduino.cli.commands.v1`)
 - Repeated responses are now in plural form (`identification_pref` -> `identification_prefs`, `platform` -> `platforms`)
 
-### arduino-cli JSON output breaking changes
+#### arduino-cli JSON output breaking changes
 
 Consumers of the JSON output of the CLI must update their clients if they use one of the following commands: