diff --git a/scene/gui/rich_text_label.cpp b/scene/gui/rich_text_label.cpp
index 973b02b3a31..44478d45cc5 100644
--- a/scene/gui/rich_text_label.cpp
+++ b/scene/gui/rich_text_label.cpp
@@ -1165,7 +1165,7 @@ int RichTextLabel::_draw_line(ItemFrame *p_frame, int p_line, const Vector2 &p_o
 			} else if (ul_started) {
 				ul_started = false;
 				float y_off = TS->shaped_text_get_underline_position(rid);
-				float underline_width = TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale;
+				float underline_width = MAX(1.0, TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale);
 				draw_line(ul_start + Vector2(0, y_off), p_ofs + Vector2(off.x, off.y + y_off), ul_color, underline_width);
 			}
 			if (_find_hint(it, nullptr) && underline_hint) {
@@ -1178,7 +1178,7 @@ int RichTextLabel::_draw_line(ItemFrame *p_frame, int p_line, const Vector2 &p_o
 			} else if (dot_ul_started) {
 				dot_ul_started = false;
 				float y_off = TS->shaped_text_get_underline_position(rid);
-				float underline_width = TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale;
+				float underline_width = MAX(1.0, TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale);
 				draw_dashed_line(dot_ul_start + Vector2(0, y_off), p_ofs + Vector2(off.x, off.y + y_off), dot_ul_color, underline_width, MAX(2.0, underline_width * 2));
 			}
 			if (_find_strikethrough(it)) {
@@ -1191,7 +1191,7 @@ int RichTextLabel::_draw_line(ItemFrame *p_frame, int p_line, const Vector2 &p_o
 			} else if (st_started) {
 				st_started = false;
 				float y_off = -TS->shaped_text_get_ascent(rid) + TS->shaped_text_get_size(rid).y / 2;
-				float underline_width = TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale;
+				float underline_width = MAX(1.0, TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale);
 				draw_line(st_start + Vector2(0, y_off), p_ofs + Vector2(off.x, off.y + y_off), st_color, underline_width);
 			}
 
@@ -1334,19 +1334,19 @@ int RichTextLabel::_draw_line(ItemFrame *p_frame, int p_line, const Vector2 &p_o
 					if (ul_started) {
 						ul_started = false;
 						float y_off = TS->shaped_text_get_underline_position(rid);
-						float underline_width = TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale;
+						float underline_width = MAX(1.0, TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale);
 						draw_line(ul_start + Vector2(0, y_off), p_ofs + Vector2(off.x, off.y + y_off), ul_color, underline_width);
 					}
 					if (dot_ul_started) {
 						dot_ul_started = false;
 						float y_off = TS->shaped_text_get_underline_position(rid);
-						float underline_width = TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale;
+						float underline_width = MAX(1.0, TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale);
 						draw_dashed_line(dot_ul_start + Vector2(0, y_off), p_ofs + Vector2(off.x, off.y + y_off), dot_ul_color, underline_width, MAX(2.0, underline_width * 2));
 					}
 					if (st_started) {
 						st_started = false;
 						float y_off = -TS->shaped_text_get_ascent(rid) + TS->shaped_text_get_size(rid).y / 2;
-						float underline_width = TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale;
+						float underline_width = MAX(1.0, TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale);
 						draw_line(st_start + Vector2(0, y_off), p_ofs + Vector2(off.x, off.y + y_off), st_color, underline_width);
 					}
 				}
@@ -1356,19 +1356,19 @@ int RichTextLabel::_draw_line(ItemFrame *p_frame, int p_line, const Vector2 &p_o
 		if (ul_started) {
 			ul_started = false;
 			float y_off = TS->shaped_text_get_underline_position(rid);
-			float underline_width = TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale;
+			float underline_width = MAX(1.0, TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale);
 			draw_line(ul_start + Vector2(0, y_off), p_ofs + Vector2(off.x, off.y + y_off), ul_color, underline_width);
 		}
 		if (dot_ul_started) {
 			dot_ul_started = false;
 			float y_off = TS->shaped_text_get_underline_position(rid);
-			float underline_width = TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale;
+			float underline_width = MAX(1.0, TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale);
 			draw_dashed_line(dot_ul_start + Vector2(0, y_off), p_ofs + Vector2(off.x, off.y + y_off), dot_ul_color, underline_width, MAX(2.0, underline_width * 2));
 		}
 		if (st_started) {
 			st_started = false;
 			float y_off = -TS->shaped_text_get_ascent(rid) + TS->shaped_text_get_size(rid).y / 2;
-			float underline_width = TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale;
+			float underline_width = MAX(1.0, TS->shaped_text_get_underline_thickness(rid) * theme_cache.base_scale);
 			draw_line(st_start + Vector2(0, y_off), p_ofs + Vector2(off.x, off.y + y_off), st_color, underline_width);
 		}
 		// Draw foreground color box