diff --git a/README.md b/README.md
index c8f17c877..2cd3ddf51 100644
--- a/README.md
+++ b/README.md
@@ -244,16 +244,16 @@ It will help if you want to know what the program is doing.
 
 If you want to run a command written in Ruby like `rake`, `rails`, `bundle`, `rspec`, and so on, you can use `rdbg -c` option.
 
-* Without `-c` option, `rdbg <name>` means that `<name>` is Ruby script and invoke it like `ruby <name>` with the debugger.
-* With `-c` option, `rdbg -c <name>` means that `<name>` is a command in `PATH` and simply invokes it with the debugger.
+* Without the `-c` option, `rdbg <name>` means that `<name>` is a Ruby script and invokes it like `ruby <name>` with the debugger.
+* With the `-c` option, `rdbg -c <name>` means that `<name>` is a command in `PATH` and simply invokes it with the debugger.
 
 Examples:
 * `rdbg -c -- rails server`
 * `rdbg -c -- bundle exec ruby foo.rb`
 * `rdbg -c -- bundle exec rake test`
-* `rdbg -c -- ruby target.rb` is same as `rdbg target.rb`
+* `rdbg -c -- ruby target.rb` is the same as `rdbg target.rb`
 
-NOTE: `--` is needed to separate the command line options for `rdbg` and invoking command. For example, `rdbg -c rake -T` is recognized like `rdbg -c -T -- rake`. It should be `rdbg -c -- rake -T`.
+NOTE: `--` is needed to separate the command line options for `rdbg` and the invoking command. For example, `rdbg -c rake -T` is recognized like `rdbg -c -T -- rake`. It should be `rdbg -c -- rake -T`.
 
 NOTE: If you want to use bundler (`bundle` command), you need to write `gem debug` line in your `Gemfile`.
 
@@ -330,7 +330,9 @@ When `rdbg --attach` connects to the debuggee, you can use any debug commands (s
 
 NOTE: If you use the `quit` command, only the remote console exits and the debuggee program continues to run (and you can connect it again). If you want to exit the debuggee program, use `kill` command.
 
-If you want to use TCP/IP for the remote debugging, you need to specify the port and host with `--port` like `rdbg --open --port 12345` and it binds to `localhost:12345`.
+If you want to use TCP/IP for the remote debugging, you need to specify the port and host with `--port` like `rdbg --open --port 12345` and it binds to `localhost:12345`. You can add an optional `--port_range` option to try multiple ports in a reliable way. For example, `rdbg --open --port 12345 --port_range 10` will try to bind to 12345, 12346, 12347, ... until it finds an available port.
+
+```shell
 
 To connect to the debuggee, you need to specify the port.
 
@@ -499,6 +501,7 @@ config set no_color true
 * REMOTE
   * `RUBY_DEBUG_OPEN` (`open`): Open remote port (same as `rdbg --open` option)
   * `RUBY_DEBUG_PORT` (`port`): TCP/IP remote debugging: port
+  * `RUBY_DEBUG_PORT_RANGE` (`port_range`): TCP/IP remote debugging: length of port range
   * `RUBY_DEBUG_HOST` (`host`): TCP/IP remote debugging: host (default: 127.0.0.1)
   * `RUBY_DEBUG_SOCK_PATH` (`sock_path`): UNIX Domain Socket remote debugging: socket path
   * `RUBY_DEBUG_SOCK_DIR` (`sock_dir`): UNIX Domain Socket remote debugging: socket directory
@@ -907,6 +910,7 @@ Debug console mode:
                                      Now rdbg, vscode and chrome is supported.
         --sock-path=SOCK_PATH        UNIX Domain socket path
         --port=PORT                  Listening TCP/IP port
+        --port-range=PORT_RANGE      Number of ports to try to connect to
         --host=HOST                  Listening TCP/IP host
         --cookie=COOKIE              Set a cookie for connection
         --session-name=NAME          Session name
diff --git a/debug.gemspec b/debug.gemspec
index 2a5891f32..f77ae68ae 100644
--- a/debug.gemspec
+++ b/debug.gemspec
@@ -14,6 +14,7 @@ Gem::Specification.new do |spec|
 
   spec.metadata["homepage_uri"] = spec.homepage
   spec.metadata["source_code_uri"] = spec.homepage
+  spec.metadata["changelog_uri"] = "#{spec.homepage}/releases/tag/v#{spec.version}"
 
   # Specify which files should be added to the gem when it is released.
   # The `git ls-files -z` loads the files in the RubyGem that have been added into git.
diff --git a/lib/debug/config.rb b/lib/debug/config.rb
index 86b9bfdc9..0fcbea7ec 100644
--- a/lib/debug/config.rb
+++ b/lib/debug/config.rb
@@ -44,6 +44,7 @@ module DEBUGGER__
     # remote setting
     open:           ['RUBY_DEBUG_OPEN',         "REMOTE: Open remote port (same as `rdbg --open` option)"],
     port:           ['RUBY_DEBUG_PORT',         "REMOTE: TCP/IP remote debugging: port"],
+    port_range:     ['RUBY_DEBUG_PORT_RANGE',   "REMOTE: TCP/IP remote debugging: length of port range"],
     host:           ['RUBY_DEBUG_HOST',         "REMOTE: TCP/IP remote debugging: host", :string, "127.0.0.1"],
     sock_path:      ['RUBY_DEBUG_SOCK_PATH',    "REMOTE: UNIX Domain Socket remote debugging: socket path"],
     sock_dir:       ['RUBY_DEBUG_SOCK_DIR',     "REMOTE: UNIX Domain Socket remote debugging: socket directory"],
@@ -352,6 +353,9 @@ def self.parse_argv argv
         o.on('--port=PORT', 'Listening TCP/IP port') do |port|
           config[:port] = port
         end
+        o.on('--port-range=PORT_RANGE', 'Number of ports to try to connect to') do |port_range|
+          config[:port_range] = port_range
+        end
         o.on('--host=HOST', 'Listening TCP/IP host') do |host|
           config[:host] = host
         end
diff --git a/lib/debug/server.rb b/lib/debug/server.rb
index 0915b5bd5..41f3bca13 100644
--- a/lib/debug/server.rb
+++ b/lib/debug/server.rb
@@ -399,6 +399,13 @@ def initialize host: nil, port: nil
           raise "Specify digits for port number"
         end
       end
+      @port_range = if @port.zero?
+        0
+      else
+        port_range_str = (CONFIG[:port_range] || "0").to_s
+        raise "Specify a positive integer <=16 for port range" unless port_range_str.match?(/\A\d+\z/) && port_range_str.to_i <= 16
+        port_range_str.to_i
+      end
       @uuid = nil # for CDP
 
       super()
@@ -452,7 +459,9 @@ def accept
           end
         end
       rescue Errno::EADDRINUSE
-        if retry_cnt < 10
+        number_of_retries = @port_range.zero? ? 10 : @port_range
+        if retry_cnt < number_of_retries
+          @port += 1 unless @port_range.zero?
           retry_cnt += 1
           sleep 0.1
           retry
diff --git a/lib/debug/server_cdp.rb b/lib/debug/server_cdp.rb
index 3826f1242..9adb09795 100644
--- a/lib/debug/server_cdp.rb
+++ b/lib/debug/server_cdp.rb
@@ -688,7 +688,7 @@ def sock skip: false
       yield $stderr
     end
 
-    def puts result=''
+    def puts result = ""
       # STDERR.puts "puts: #{result}"
       # send_event 'output', category: 'stderr', output: "PUTS!!: " + result.to_s
     end
diff --git a/lib/debug/server_dap.rb b/lib/debug/server_dap.rb
index 87c22ca45..7502182a4 100644
--- a/lib/debug/server_dap.rb
+++ b/lib/debug/server_dap.rb
@@ -501,7 +501,7 @@ def respond req, res
       send_response(req, **res)
     end
 
-    def puts result
+    def puts result = ""
       # STDERR.puts "puts: #{result}"
       send_event 'output', category: 'console', output: "#{result&.chomp}\n"
     end
diff --git a/lib/debug/thread_client.rb b/lib/debug/thread_client.rb
index 80a434b0c..1d35d754a 100644
--- a/lib/debug/thread_client.rb
+++ b/lib/debug/thread_client.rb
@@ -44,7 +44,7 @@ def skip_location?(loc)
   end
 
   module GlobalVariablesHelper
-    SKIP_GLOBAL_LIST = %i[$= $KCODE $-K $SAFE].freeze
+    SKIP_GLOBAL_LIST = %i[$= $KCODE $-K $SAFE $FILENAME].freeze
     def safe_global_variables
       global_variables.reject{|name| SKIP_GLOBAL_LIST.include? name }
     end
diff --git a/lib/debug/version.rb b/lib/debug/version.rb
index cf7b7b23e..f1d1e9467 100644
--- a/lib/debug/version.rb
+++ b/lib/debug/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module DEBUGGER__
-  VERSION = "1.9.2"
+  VERSION = "1.10.0"
 end
diff --git a/misc/README.md.erb b/misc/README.md.erb
index e6751997b..90bb57e17 100644
--- a/misc/README.md.erb
+++ b/misc/README.md.erb
@@ -244,16 +244,16 @@ It will help if you want to know what the program is doing.
 
 If you want to run a command written in Ruby like `rake`, `rails`, `bundle`, `rspec`, and so on, you can use `rdbg -c` option.
 
-* Without `-c` option, `rdbg <name>` means that `<name>` is Ruby script and invoke it like `ruby <name>` with the debugger.
-* With `-c` option, `rdbg -c <name>` means that `<name>` is a command in `PATH` and simply invokes it with the debugger.
+* Without the `-c` option, `rdbg <name>` means that `<name>` is a Ruby script and invokes it like `ruby <name>` with the debugger.
+* With the `-c` option, `rdbg -c <name>` means that `<name>` is a command in `PATH` and simply invokes it with the debugger.
 
 Examples:
 * `rdbg -c -- rails server`
 * `rdbg -c -- bundle exec ruby foo.rb`
 * `rdbg -c -- bundle exec rake test`
-* `rdbg -c -- ruby target.rb` is same as `rdbg target.rb`
+* `rdbg -c -- ruby target.rb` is the same as `rdbg target.rb`
 
-NOTE: `--` is needed to separate the command line options for `rdbg` and invoking command. For example, `rdbg -c rake -T` is recognized like `rdbg -c -T -- rake`. It should be `rdbg -c -- rake -T`.
+NOTE: `--` is needed to separate the command line options for `rdbg` and the invoking command. For example, `rdbg -c rake -T` is recognized like `rdbg -c -T -- rake`. It should be `rdbg -c -- rake -T`.
 
 NOTE: If you want to use bundler (`bundle` command), you need to write `gem debug` line in your `Gemfile`.
 
@@ -330,7 +330,9 @@ When `rdbg --attach` connects to the debuggee, you can use any debug commands (s
 
 NOTE: If you use the `quit` command, only the remote console exits and the debuggee program continues to run (and you can connect it again). If you want to exit the debuggee program, use `kill` command.
 
-If you want to use TCP/IP for the remote debugging, you need to specify the port and host with `--port` like `rdbg --open --port 12345` and it binds to `localhost:12345`.
+If you want to use TCP/IP for the remote debugging, you need to specify the port and host with `--port` like `rdbg --open --port 12345` and it binds to `localhost:12345`. You can add an optional `--port_range` option to try multiple ports in a reliable way. For example, `rdbg --open --port 12345 --port_range 10` will try to bind to 12345, 12346, 12347, ... until it finds an available port.
+
+```shell
 
 To connect to the debuggee, you need to specify the port.
 
diff --git a/test/console/catch_test.rb b/test/console/catch_test.rb
index 164ac4288..d4addf997 100644
--- a/test/console/catch_test.rb
+++ b/test/console/catch_test.rb
@@ -44,29 +44,29 @@ def test_catch_command_isnt_repeatable
 
     def test_catch_works_with_command
       debug_code(program) do
-        type 'catch ZeroDivisionError pre: p "1234"'
+        type 'catch ZeroDivisionError pre: p "catching zero division"'
         assert_line_text(/#0  BP - Catch  "ZeroDivisionError"/)
         type 'continue'
-        assert_line_text(/1234/)
+        assert_line_text(/catching zero division/)
         type 'continue'
         type 'continue'
       end
 
       debug_code(program) do
-        type 'catch ZeroDivisionError do: p "1234"'
+        type 'catch ZeroDivisionError do: p "catching zero division"'
         assert_line_text(/#0  BP - Catch  "ZeroDivisionError"/)
         type 'continue'
-        assert_line_text(/1234/)
+        assert_line_text(/catching zero division/)
         type 'continue'
       end
     end
 
     def test_catch_works_with_condition
       debug_code(program) do
-        type 'catch ZeroDivisionError if: a == 2 do: p "1234"'
+        type 'catch ZeroDivisionError if: a == 2 do: p "catching zero division"'
         assert_line_text(/#0  BP - Catch  "ZeroDivisionError"/)
         type 'continue'
-        assert_no_line_text(/1234/)
+        assert_no_line_text(/catching zero division/)
         type 'continue'
       end
     end
diff --git a/test/console/irb_test.rb b/test/console/irb_test.rb
index 857d02dfd..746f9acdb 100644
--- a/test/console/irb_test.rb
+++ b/test/console/irb_test.rb
@@ -47,7 +47,7 @@ def test_irb_command_switches_console_to_irb
       debug_code(program, remote: false) do
         type 'irb'
         type '123'
-        assert_line_text 'irb:rdbg(main):002> 123'
+        assert_raw_line_text 'irb:rdbg(main):002> 123'
         type 'irb_info'
         assert_line_text('IRB version:')
         type 'next'
@@ -67,7 +67,7 @@ def test_irb_console_config_activates_irb
 
       debug_code(program, remote: false) do
         type '123'
-        assert_line_text 'irb:rdbg(main):002> 123'
+        assert_raw_line_text 'irb:rdbg(main):002> 123'
         type 'irb_info'
         assert_line_text('IRB version:')
         type 'next'
diff --git a/test/console/print_test.rb b/test/console/print_test.rb
index 3f9702b76..16f5c4436 100644
--- a/test/console/print_test.rb
+++ b/test/console/print_test.rb
@@ -15,7 +15,7 @@ def test_p_prints_the_expression
       debug_code(program) do
         type "c"
         type "p h"
-        assert_line_text('{:foo=>"bar"}')
+        assert_line_text({ foo: "bar" }.inspect)
         type "c"
       end
     end
@@ -24,7 +24,7 @@ def test_pp_pretty_prints_the_expression
       debug_code(program) do
         type "c"
         type "pp h"
-        assert_line_text([/\{:foo=>/, /"bar"\}/])
+        assert_line_text({ foo: "bar" }.pretty_print_inspect)
         type "c"
       end
     end
diff --git a/test/support/console_test_case.rb b/test/support/console_test_case.rb
index f7e62fb4b..187506e99 100644
--- a/test/support/console_test_case.rb
+++ b/test/support/console_test_case.rb
@@ -225,7 +225,12 @@ def prepare_test_environment(program, test_steps, &block)
       @scenario = []
       test_steps.call
       @scenario.freeze
-      inject_lib_to_load_path
+
+      ENV['RUBYOPT'] = "-I #{__dir__}/../../lib"
+
+      if ENV.key?('BUNDLE_GEMFILE')
+        ENV["RUBYOPT"] += " -rbundler/setup"
+      end
 
       block.call
 
@@ -283,7 +288,7 @@ def run_rdbg program, options: nil, rubyopt: nil, &test_steps
       prepare_test_environment(program, test_steps) do
         test_info = TestInfo.new(dup_scenario, 'LOCAL', /\(rdbg\)/)
         cmd = "#{RDBG_EXECUTABLE} #{options} -- #{temp_file_path}"
-        cmd = "RUBYOPT=#{rubyopt} #{cmd}" if rubyopt
+        ENV["RUBYOPT"] += " #{rubyopt}" if rubyopt
         run_test_scenario cmd, test_info
       end
     end
@@ -301,10 +306,6 @@ def new_thread &block
       end
     end
 
-    def inject_lib_to_load_path
-      ENV['RUBYOPT'] = "-I #{__dir__}/../../lib"
-    end
-
     def assert_empty_queue test_info, exception: nil
       message = "Expected all commands/assertions to be executed. Still have #{test_info.queue.length} left."
       if exception
diff --git a/test/support/test_case.rb b/test/support/test_case.rb
index 5ff8a2e27..2d1d26f96 100644
--- a/test/support/test_case.rb
+++ b/test/support/test_case.rb
@@ -180,6 +180,9 @@ def setup_remote_debuggee(cmd)
           msg1 = true
         when /\ADEBUGGER: wait for debugger connection/
           msg2 = true
+        else
+          # unknown lines
+          STDERR.puts "> #{line}"
         end
 
         break if msg1 && msg2