diff --git a/config_panel.toml b/config_panel.toml
index b3955c3..40ae334 100644
--- a/config_panel.toml
+++ b/config_panel.toml
@@ -30,21 +30,21 @@ name = "My webapp configuration"
         ask = "Memory footprint of the service?"
         choices = ["low", "medium", "high", "specific"]
         default = "low"
-        visible = "! match(phpversion, 'none')"
+        visible = '! match(phpversion, "none")'
         help = "low <= 20Mb per pool. medium between 20Mb and 40Mb per pool. high > 40Mb per pool.<br>Use specific to set a value with the following option."
 
         [main.php_fpm_config.free_footprint]
         ask = "Memory footprint of the service?"
         type = "number"
         default = "0"
-        visible = "match(fpm_footprint, 'specific') && ! match(phpversion, 'none')"
+        visible = 'match(fpm_footprint, "specific") && ! match(phpversion, "none")'
         help = "Free field to specify exactly the footprint in Mb if you don't want to use one of the three previous values."
 
         [main.php_fpm_config.fpm_usage]
         ask = "Expected usage of the service?"
         choices = ["low", "medium", "high"]
         default = "low"
-        visible = "! match(phpversion, 'none')"
+        visible = '! match(phpversion, "none")'
         help = "low: Personal usage, behind the SSO. No RAM footprint when not used, but the impact on the processor can be high if many users are using the service.<br>medium: Low usage, few people or/and publicly accessible. Low RAM footprint, medium processor footprint when used.<br>high: High usage, frequently visited website. High RAM footprint, but lower on processor usage and quickly responding."
 
 # TODO: Add protected_path as tags, which are created as permission "label (path)", so admin can protect a specific path